Index
Why cleaning the car is the most profitable investment
Exterior step-by-step: top to bottom
Interior step-by-step: what the buyer smells and touches
Engine: how far to go
Boot: the space many forget
Products you need and how much they cost
Professional vs home cleaning: when to pay
Frequently asked questions
A dirty car is not worth less than a clean one. But a buyer will pay less for it. It is a perception, not a mechanical reality, but perceptions are what determine the offers.
A seller who cleans their car thoroughly before showing it or taking photographs is investing between 2 and 4 hours of work (or between £30 and £80 if they pay for a professional valet) in exchange for a perception of care that translates directly into hundreds of pounds more in the price. It is the investment with the highest return in the entire selling process, far above any repair, upgrade, or listing strategy.
Cleaning is part of the comprehensive preparation of the car. Check our complete guide on how to prepare your car to sell it for more money.
In this guide, we explain exactly how to clean your car for sale, in what order, with which products, and when it is worth delegating to a professional.
Exterior step-by-step: top to bottom
Exterior cleaning follows a logical order: top to bottom and from the dirtiest to the least dirty. If you clean in any other order, the dirt from the upper parts will fall onto the ones you have already cleaned.
Step 1: Pre-rinse
Before touching the bodywork, rinse the entire car with pressure water (a hose or pressure washer). The goal is to remove dust, sand, and loose particles that, if dragged with a sponge, will scratch the paint. Pay special attention to the wheel arches, the bottoms of the doors, and the area under the bumpers, where most dirt accumulates.
Step 2: Wheels and tyres first
The wheels are the dirtiest area of the car (brake dust, mud, road grime). If you clean them after the bodywork, the splashes of dirt from the wheels will stain the panels you have already washed.
Apply a specific wheel cleaner (spray), let it act for 2-3 minutes, and scrub with a soft-bristled brush. Rinse with pressure water. For the tyres, use a stiffer brush and soap. Once dry, apply a tyre dressing that gives them a matte black finish that looks brand new.
Step 3: Washing the bodywork
Fill a bucket with water and car shampoo (do not use washing-up liquid, which is too aggressive and strips the protective wax). Use a microfibre mitt or a soft sponge. Wash panel by panel, from top to bottom, rinsing the sponge frequently so as not to drag dirt.
Areas that are usually forgotten: the door frames (open them and clean the edge), the roof rain gutters, the area under the number plate, the window rubber seals, and the wing mirrors.
Step 4: Rinsing and drying
Rinse the entire car with clean water, from top to bottom. Dry with large microfibre towels (never with normal fabric cloths, which scratch). Drying is important because water droplets leave limescale marks when they evaporate, especially on dark cars.
Step 5: Windows
Clean all the windows on the outside with glass cleaner and a microfibre cloth. The glass should be left smear-free. Pay special attention to the windscreen: it is the most visible window and the one that gets the dirtiest.
Step 6: Quick polishing of superficial scratches (optional)
If the bodywork has superficial scratches (which can be felt with a fingernail but have not reached the primer), a quick polish with a product like Meguiar's or Turtle Wax can remove them. Apply with a microfibre cloth using circular motions and buff off the excess with another clean cloth.
Do not attempt to polish deep scratches (where the grey primer or metal is visible): they need professional touch-up and home polish will not work.
Not repairing cheap scratches is one of the mistakes that make you sell your car for less money.
Step 7: Headlights (if they are cloudy)
Cloudy or yellowed headlights visually age the car by several years. A headlight restoration kit (£10-£15 in any car accessory shop) includes various grits of sandpaper and a polish that restores transparency to the polycarbonate. The process takes 15-20 minutes per headlight and the result is spectacular.
If you do not want to do it yourself, a detailing workshop charges between £20 and £40 to restore both headlights.
Interior step-by-step: what the buyer smells and touches
The interior is where the sale is won or lost. The buyer sits inside, touches the steering wheel, looks at the dashboard, and breathes. If any of that fails, the perception collapses.
Step 1: Remove everything
Empty the car completely. Glovebox, trays, cup holders, door pockets, boot, under the seats. Remove absolutely everything: documents, coins, chewing gum, papers, chargers, air fresheners, seat covers, extra mats. The car must look as if it has just left the factory.
Step 2: Complete vacuum
Vacuum the entire interior with attention to detail. The floor (including the areas under the seats and the pedals), the seats (including the side seams and the gap between the backrest and the seat cushion), the entire boot, the dashboard trays, and the door pockets.
If you use a household vacuum cleaner, it works. If you can use one at a petrol station (£2-£3, more power), even better. The important thing is that not a single crumb, pet hair, or grain of sand remains.
Step 3: Dashboard and plastics
Use an all-purpose interior cleaner (spray or wipes) and a microfibre cloth. Clean all plastic surfaces: dashboard, centre console, door panels, steering wheel, gear stick, screen surround, air vents.
Do not use excessively shiny products (such as silicone). A dashboard that is too shiny looks artificial and leaves sticky residues. The ideal finish is matte and clean: it looks original, not "varnished".
The air vents are a nest for dust. Use a soft brush or a cotton bud to reach the slats.
Step 4: Screens and instrument cluster
Touchscreens accumulate fingerprints that are especially visible when they are turned off. Clean with a dry or slightly damp microfibre cloth (never with alcohol-based glass cleaners, which can damage the screen's anti-reflective coating).
The instrument cluster (analogue or digital) should also be cleaned with a dry microfibre cloth. Make sure it is left dust and smudge-free.
Step 5: Upholstery
If it is fabric. After vacuuming, apply an upholstery cleaner to any stained areas. Scrub with a soft brush, let it work, and wipe away with a damp cloth. For tough stains, a steam upholstery cleaner (which can be rented for £15-£20 a day) works miracles.
If it is leather. Clean first with a specific leather soap (not with all-purpose products that can dry it out). Afterwards, apply a leather conditioner that hydrates and restores flexibility. Dry, cracked leather knocks hundreds of pounds off the price of a premium car. Hydrated, shiny leather adds value.
Steering wheel. This is the surface that is touched the most and accumulates the most wear. Clean with the appropriate product (all-purpose for a plastic steering wheel, leather soap for a leather steering wheel). A clean steering wheel is immediately noticed upon touch.
Step 6: Windows on the inside
The interior windows accumulate a greasy film (from the outgassing of the dashboard plastics) which is not visible to the naked eye but creates a haze noticed in sunlight. Clean all interior windows with glass cleaner and a clean microfibre cloth.
Step 7: Odours
Odour is the hardest factor to control and the one with the most negative impact. A car that smells of tobacco, dog, food, or dampness generates a visceral rejection that no photo or description can compensate for.
Mild odours. Complete vacuum + upholstery cleaning + airing out for a few hours with the windows open. Bicarbonate of soda sprinkled over the upholstery overnight and vacuumed the next day absorbs mild odours.
Moderate odours (tobacco, pet). You need an ozone treatment. An ozone generator eliminates organic odours at a molecular level. Many valeting and detailing workshops offer this service for £30-£50. It is the most effective investment for removing stubborn odours.
Severe odours (damp, mould). This indicates a water ingress issue that must be resolved before cleaning. If there is persistent dampness, find the source (windscreen seal, sunroof drain, boot seal) and repair it. Cleaning over an unresolved damp issue is throwing money away.
Never mask odours with air fresheners. A strong air freshener on top of a tobacco smell creates a blend worse than the original odour. The buyer will detect it instantly and think "they are trying to hide something". Eliminate the odour; do not cover it up.
Once clean, take the photos. View how to take the best photos to sell your car.
Engine: how far to go
Cleaning the engine is not essential for the sale, but a reasonably clean engine bay creates a good impression if the buyer lifts the bonnet (and many do).
The bare minimum. Remove leaves, accumulated dirt, and visible debris with a dry cloth or vacuum cleaner. Clean the engine cover (if plastic) with a damp cloth. It is a 5-minute job that improves the visual impression.
The recommended way. A degreasing spray applied to the visible areas of the engine (not on electrical components) and a gentle rinse with water removes the layer of grease and accumulated dust. Allow to dry before closing the bonnet.
What you must not do. Do not use a pressure washer directly on the engine. Pressure water can damage electrical connectors, sensors, and electronic components. A gentle rinse with a hose (without pressure) is sufficient.
In addition to cleaning, there are mechanical points to check. Consult what to check on your car before selling it.
Boot: the space many forget
The boot is a spot that many sellers overlook, but the buyer always opens it.
Empty it completely. Remove everything, including the parcel shelf or load cover (to clean underneath) and the bottom carpet (to check for dampness or oxidation).
Vacuum thoroughly. The corners of the boot accumulate sand, crumbs, and dirt that are instantly visible.
Check the spare wheel. If your car has a spare wheel, check that it is inflated and in good condition. If it has a puncture repair kit, check that it is complete and has not expired (the sealant liquid expires). A buyer who opens the wheel well and finds everything in order gains confidence.
Eliminate odours. If the boot smells of damp, look for the source (tailgate seal, sunroof drain, ingress through the rear light clusters). A boot with a damp smell raises suspicion that the car has had a leak or a sealing problem.
Products you need and how much they cost
Product | Price | What it's for |
|---|---|---|
Car shampoo | £5-£8 | Exterior wash |
Wheel cleaner (spray) | £5-£8 | Wheels |
Tyre dressing | £4-£6 | Black tyres |
Glass cleaner | £3-£5 | Interior and exterior windows |
Multipurpose interior cleaner | £5-£8 | Dashboard, plastics |
Leather cleaner/conditioner | £8-£12 | Only if leather upholstery |
Headlight restoration kit | £10-£15 | Only if cloudy headlights |
Scratch polish | £8-£12 | Only if superficial scratches |
Microfibre cloths (pack of 5-10) | £5-£10 | Everything |
Microfibre wash mitt | £5-£8 | Bodywork wash |
Total if you buy everything | £50-£90 | |
Total if you already have basics | £15-£30 |
Most of these products will last you for several cleans. The real investment for a single pre-sale clean is £15-£30 if you already have the basics (bucket, sponge, vacuum cleaner).
Professional vs home cleaning: when to pay
Do it yourself if:
Your car is basic to mid-range (under £15,000). The return on a professional valet does not justify the extra cost compared to doing it yourself. You have 3-4 hours available on a weekend. You enjoy the process (or at least do not mind doing it).
Pay a professional if:
Your car is premium or worth more than £20,000. A professional interior detail (£80-£150) can add proportionally more to the price of an expensive car than a cheap one. The interior has deeply embedded odours that need an ozone treatment. The leather is dry and needs professional hydration treatment. You do not have the time or interest and prefer to invest money instead of time.
For premium cars, the investment in professional detailing is recovered. Consult how to sell a premium or high-end car.
Professional cleaning options:
Manual exterior hand wash: £15-£30. Complete interior clean: £30-£60. Exterior + interior: £40-£80. Full detail (paint correction + interior + engine): £150-£400. Ozone treatment for odours: £30-£50.
For most cars under £15,000, a professional exterior + interior wash (£40-£80) gives an excellent result with minimal effort. For premium cars, an interior detail (£80-£150) is an investment that is recovered in the selling price.
Dealcar: value your car for free and receive offers from dealerships
With your car clean and ready, the next step is knowing what it's worth. With Dealcar, you can value your car for free in less than 30 seconds and receive offers from more than 1,000 dealerships competing with each other.
A clean and well-presented car generates higher offers than a neglected one, even among professional dealerships: a car that looks cared for requires less investment to resell, which is reflected in the offer.
100% free for you. No fees or hidden costs.
Get paid before handing over the keys. Bank transfer before delivering the car.
Home collection of the car. No travel required.
No paperwork. The buyer handles the transfer, DVLA, and all the paperwork.
On average, £1,400 more than selling on Wallapop.
Over 12,000 cars sold and an average rating of 4.9 out of 5.
Use the free Dealcar valuation tool.
Frequently asked questions
How much does it cost to clean the car to sell? If you do it yourself, between £15 and £30 in products (if you already have the basics) and 3-4 hours of work. If you pay for a professional exterior + interior valet, between £40 and £80. If you need premium detailing or ozone treatment, between £80 and £200.
Is a petrol station car wash tunnel enough? No. The automatic car wash cleans the bodywork superficially but does not reach the areas that make a difference: door frames, wheels in depth, interior, interior windows, boot. A hand wash (yours or professional) gives an incomparably better result.
How do I remove tobacco smell? Upholstery cleaning + vacuuming + airing out removes superficial odours. For embedded tobacco, you need an ozone treatment (£30-£50 in a detailing studio). Do not use air fresheners to cover it: the buyer will detect it and it raises more distrust than the smell itself.
Is it worth restoring the headlights? Yes, if they are cloudy. It is one of the investments with the highest visual impact: £10-£15 and 30 minutes of work that rejuvenate the look of the car by several years. The buyer immediately notices the difference between transparent headlights and yellowed ones.
Should I clean the engine? It is not essential, but a reasonably clean engine adds points if the buyer opens the bonnet. A 5-minute superficial clean (removing leaves and wiping the engine cover) is enough. Do not use a pressure washer directly on the engine.
Index
Why cleaning the car is the most profitable investment
Exterior step-by-step: top to bottom
Interior step-by-step: what the buyer smells and touches
Engine: how far to go
Boot: the space many forget
Products you need and how much they cost
Professional vs home cleaning: when to pay
Frequently asked questions
A dirty car is not worth less than a clean one. But a buyer will pay less for it. It is a perception, not a mechanical reality, but perceptions are what determine the offers.
A seller who cleans their car thoroughly before showing it or taking photographs is investing between 2 and 4 hours of work (or between £30 and £80 if they pay for a professional valet) in exchange for a perception of care that translates directly into hundreds of pounds more in the price. It is the investment with the highest return in the entire selling process, far above any repair, upgrade, or listing strategy.
Cleaning is part of the comprehensive preparation of the car. Check our complete guide on how to prepare your car to sell it for more money.
In this guide, we explain exactly how to clean your car for sale, in what order, with which products, and when it is worth delegating to a professional.
Exterior step-by-step: top to bottom
Exterior cleaning follows a logical order: top to bottom and from the dirtiest to the least dirty. If you clean in any other order, the dirt from the upper parts will fall onto the ones you have already cleaned.
Step 1: Pre-rinse
Before touching the bodywork, rinse the entire car with pressure water (a hose or pressure washer). The goal is to remove dust, sand, and loose particles that, if dragged with a sponge, will scratch the paint. Pay special attention to the wheel arches, the bottoms of the doors, and the area under the bumpers, where most dirt accumulates.
Step 2: Wheels and tyres first
The wheels are the dirtiest area of the car (brake dust, mud, road grime). If you clean them after the bodywork, the splashes of dirt from the wheels will stain the panels you have already washed.
Apply a specific wheel cleaner (spray), let it act for 2-3 minutes, and scrub with a soft-bristled brush. Rinse with pressure water. For the tyres, use a stiffer brush and soap. Once dry, apply a tyre dressing that gives them a matte black finish that looks brand new.
Step 3: Washing the bodywork
Fill a bucket with water and car shampoo (do not use washing-up liquid, which is too aggressive and strips the protective wax). Use a microfibre mitt or a soft sponge. Wash panel by panel, from top to bottom, rinsing the sponge frequently so as not to drag dirt.
Areas that are usually forgotten: the door frames (open them and clean the edge), the roof rain gutters, the area under the number plate, the window rubber seals, and the wing mirrors.
Step 4: Rinsing and drying
Rinse the entire car with clean water, from top to bottom. Dry with large microfibre towels (never with normal fabric cloths, which scratch). Drying is important because water droplets leave limescale marks when they evaporate, especially on dark cars.
Step 5: Windows
Clean all the windows on the outside with glass cleaner and a microfibre cloth. The glass should be left smear-free. Pay special attention to the windscreen: it is the most visible window and the one that gets the dirtiest.
Step 6: Quick polishing of superficial scratches (optional)
If the bodywork has superficial scratches (which can be felt with a fingernail but have not reached the primer), a quick polish with a product like Meguiar's or Turtle Wax can remove them. Apply with a microfibre cloth using circular motions and buff off the excess with another clean cloth.
Do not attempt to polish deep scratches (where the grey primer or metal is visible): they need professional touch-up and home polish will not work.
Not repairing cheap scratches is one of the mistakes that make you sell your car for less money.
Step 7: Headlights (if they are cloudy)
Cloudy or yellowed headlights visually age the car by several years. A headlight restoration kit (£10-£15 in any car accessory shop) includes various grits of sandpaper and a polish that restores transparency to the polycarbonate. The process takes 15-20 minutes per headlight and the result is spectacular.
If you do not want to do it yourself, a detailing workshop charges between £20 and £40 to restore both headlights.
Interior step-by-step: what the buyer smells and touches
The interior is where the sale is won or lost. The buyer sits inside, touches the steering wheel, looks at the dashboard, and breathes. If any of that fails, the perception collapses.
Step 1: Remove everything
Empty the car completely. Glovebox, trays, cup holders, door pockets, boot, under the seats. Remove absolutely everything: documents, coins, chewing gum, papers, chargers, air fresheners, seat covers, extra mats. The car must look as if it has just left the factory.
Step 2: Complete vacuum
Vacuum the entire interior with attention to detail. The floor (including the areas under the seats and the pedals), the seats (including the side seams and the gap between the backrest and the seat cushion), the entire boot, the dashboard trays, and the door pockets.
If you use a household vacuum cleaner, it works. If you can use one at a petrol station (£2-£3, more power), even better. The important thing is that not a single crumb, pet hair, or grain of sand remains.
Step 3: Dashboard and plastics
Use an all-purpose interior cleaner (spray or wipes) and a microfibre cloth. Clean all plastic surfaces: dashboard, centre console, door panels, steering wheel, gear stick, screen surround, air vents.
Do not use excessively shiny products (such as silicone). A dashboard that is too shiny looks artificial and leaves sticky residues. The ideal finish is matte and clean: it looks original, not "varnished".
The air vents are a nest for dust. Use a soft brush or a cotton bud to reach the slats.
Step 4: Screens and instrument cluster
Touchscreens accumulate fingerprints that are especially visible when they are turned off. Clean with a dry or slightly damp microfibre cloth (never with alcohol-based glass cleaners, which can damage the screen's anti-reflective coating).
The instrument cluster (analogue or digital) should also be cleaned with a dry microfibre cloth. Make sure it is left dust and smudge-free.
Step 5: Upholstery
If it is fabric. After vacuuming, apply an upholstery cleaner to any stained areas. Scrub with a soft brush, let it work, and wipe away with a damp cloth. For tough stains, a steam upholstery cleaner (which can be rented for £15-£20 a day) works miracles.
If it is leather. Clean first with a specific leather soap (not with all-purpose products that can dry it out). Afterwards, apply a leather conditioner that hydrates and restores flexibility. Dry, cracked leather knocks hundreds of pounds off the price of a premium car. Hydrated, shiny leather adds value.
Steering wheel. This is the surface that is touched the most and accumulates the most wear. Clean with the appropriate product (all-purpose for a plastic steering wheel, leather soap for a leather steering wheel). A clean steering wheel is immediately noticed upon touch.
Step 6: Windows on the inside
The interior windows accumulate a greasy film (from the outgassing of the dashboard plastics) which is not visible to the naked eye but creates a haze noticed in sunlight. Clean all interior windows with glass cleaner and a clean microfibre cloth.
Step 7: Odours
Odour is the hardest factor to control and the one with the most negative impact. A car that smells of tobacco, dog, food, or dampness generates a visceral rejection that no photo or description can compensate for.
Mild odours. Complete vacuum + upholstery cleaning + airing out for a few hours with the windows open. Bicarbonate of soda sprinkled over the upholstery overnight and vacuumed the next day absorbs mild odours.
Moderate odours (tobacco, pet). You need an ozone treatment. An ozone generator eliminates organic odours at a molecular level. Many valeting and detailing workshops offer this service for £30-£50. It is the most effective investment for removing stubborn odours.
Severe odours (damp, mould). This indicates a water ingress issue that must be resolved before cleaning. If there is persistent dampness, find the source (windscreen seal, sunroof drain, boot seal) and repair it. Cleaning over an unresolved damp issue is throwing money away.
Never mask odours with air fresheners. A strong air freshener on top of a tobacco smell creates a blend worse than the original odour. The buyer will detect it instantly and think "they are trying to hide something". Eliminate the odour; do not cover it up.
Once clean, take the photos. View how to take the best photos to sell your car.
Engine: how far to go
Cleaning the engine is not essential for the sale, but a reasonably clean engine bay creates a good impression if the buyer lifts the bonnet (and many do).
The bare minimum. Remove leaves, accumulated dirt, and visible debris with a dry cloth or vacuum cleaner. Clean the engine cover (if plastic) with a damp cloth. It is a 5-minute job that improves the visual impression.
The recommended way. A degreasing spray applied to the visible areas of the engine (not on electrical components) and a gentle rinse with water removes the layer of grease and accumulated dust. Allow to dry before closing the bonnet.
What you must not do. Do not use a pressure washer directly on the engine. Pressure water can damage electrical connectors, sensors, and electronic components. A gentle rinse with a hose (without pressure) is sufficient.
In addition to cleaning, there are mechanical points to check. Consult what to check on your car before selling it.
Boot: the space many forget
The boot is a spot that many sellers overlook, but the buyer always opens it.
Empty it completely. Remove everything, including the parcel shelf or load cover (to clean underneath) and the bottom carpet (to check for dampness or oxidation).
Vacuum thoroughly. The corners of the boot accumulate sand, crumbs, and dirt that are instantly visible.
Check the spare wheel. If your car has a spare wheel, check that it is inflated and in good condition. If it has a puncture repair kit, check that it is complete and has not expired (the sealant liquid expires). A buyer who opens the wheel well and finds everything in order gains confidence.
Eliminate odours. If the boot smells of damp, look for the source (tailgate seal, sunroof drain, ingress through the rear light clusters). A boot with a damp smell raises suspicion that the car has had a leak or a sealing problem.
Products you need and how much they cost
Product | Price | What it's for |
|---|---|---|
Car shampoo | £5-£8 | Exterior wash |
Wheel cleaner (spray) | £5-£8 | Wheels |
Tyre dressing | £4-£6 | Black tyres |
Glass cleaner | £3-£5 | Interior and exterior windows |
Multipurpose interior cleaner | £5-£8 | Dashboard, plastics |
Leather cleaner/conditioner | £8-£12 | Only if leather upholstery |
Headlight restoration kit | £10-£15 | Only if cloudy headlights |
Scratch polish | £8-£12 | Only if superficial scratches |
Microfibre cloths (pack of 5-10) | £5-£10 | Everything |
Microfibre wash mitt | £5-£8 | Bodywork wash |
Total if you buy everything | £50-£90 | |
Total if you already have basics | £15-£30 |
Most of these products will last you for several cleans. The real investment for a single pre-sale clean is £15-£30 if you already have the basics (bucket, sponge, vacuum cleaner).
Professional vs home cleaning: when to pay
Do it yourself if:
Your car is basic to mid-range (under £15,000). The return on a professional valet does not justify the extra cost compared to doing it yourself. You have 3-4 hours available on a weekend. You enjoy the process (or at least do not mind doing it).
Pay a professional if:
Your car is premium or worth more than £20,000. A professional interior detail (£80-£150) can add proportionally more to the price of an expensive car than a cheap one. The interior has deeply embedded odours that need an ozone treatment. The leather is dry and needs professional hydration treatment. You do not have the time or interest and prefer to invest money instead of time.
For premium cars, the investment in professional detailing is recovered. Consult how to sell a premium or high-end car.
Professional cleaning options:
Manual exterior hand wash: £15-£30. Complete interior clean: £30-£60. Exterior + interior: £40-£80. Full detail (paint correction + interior + engine): £150-£400. Ozone treatment for odours: £30-£50.
For most cars under £15,000, a professional exterior + interior wash (£40-£80) gives an excellent result with minimal effort. For premium cars, an interior detail (£80-£150) is an investment that is recovered in the selling price.
Dealcar: value your car for free and receive offers from dealerships
With your car clean and ready, the next step is knowing what it's worth. With Dealcar, you can value your car for free in less than 30 seconds and receive offers from more than 1,000 dealerships competing with each other.
A clean and well-presented car generates higher offers than a neglected one, even among professional dealerships: a car that looks cared for requires less investment to resell, which is reflected in the offer.
100% free for you. No fees or hidden costs.
Get paid before handing over the keys. Bank transfer before delivering the car.
Home collection of the car. No travel required.
No paperwork. The buyer handles the transfer, DVLA, and all the paperwork.
On average, £1,400 more than selling on Wallapop.
Over 12,000 cars sold and an average rating of 4.9 out of 5.
Use the free Dealcar valuation tool.
Frequently asked questions
How much does it cost to clean the car to sell? If you do it yourself, between £15 and £30 in products (if you already have the basics) and 3-4 hours of work. If you pay for a professional exterior + interior valet, between £40 and £80. If you need premium detailing or ozone treatment, between £80 and £200.
Is a petrol station car wash tunnel enough? No. The automatic car wash cleans the bodywork superficially but does not reach the areas that make a difference: door frames, wheels in depth, interior, interior windows, boot. A hand wash (yours or professional) gives an incomparably better result.
How do I remove tobacco smell? Upholstery cleaning + vacuuming + airing out removes superficial odours. For embedded tobacco, you need an ozone treatment (£30-£50 in a detailing studio). Do not use air fresheners to cover it: the buyer will detect it and it raises more distrust than the smell itself.
Is it worth restoring the headlights? Yes, if they are cloudy. It is one of the investments with the highest visual impact: £10-£15 and 30 minutes of work that rejuvenate the look of the car by several years. The buyer immediately notices the difference between transparent headlights and yellowed ones.
Should I clean the engine? It is not essential, but a reasonably clean engine adds points if the buyer opens the bonnet. A 5-minute superficial clean (removing leaves and wiping the engine cover) is enough. Do not use a pressure washer directly on the engine.
