Index
Why measuring is part of the job, not an option
The essential metrics of a VLA campaign
How to interpret each metric in the context of a dealership
Signs that the campaign needs adjustment
Where to find the data: Google Ads, Merchant Center and Analytics
How often to review and what to do in each review
The metric that matters most: cost per lead vs cost per sale
Frequently Asked Questions
Why measuring is part of the job, not an option
A Google Vehicle Ads campaign that is not measured could be performing well or poorly: without data, there is no way of knowing. But even more importantly, without measurement there is no way to improve it. The Performance Max algorithm that manages VLAs learns and optimises over time, but only if it receives clear conversion signals: which clicks ended in a lead, which ones didn't, which vehicle detail pages convert best and which ones cause visitors to bounce.
A dealership that measures has three concrete advantages. First, it can identify if the budget is generating leads at a reasonable cost or if there is an issue somewhere in the funnel. Second, it can scale investment with confidence once the data confirms it works. Third, it can detect and correct issues before they consume budget for weeks without results.
To understand the full context of how VLAs work before diving deep into the metrics, you can review the complete guide to Google Vehicle Ads for dealerships.
The essential metrics of a VLA campaign
Impressions. How many times your ad has been shown. A low number of impressions indicates that your budget is too limited, that the feed has too few vehicles, or that relevant searches in your area have low volume.
Clicks. How many times someone has clicked on your ad to reach the vehicle detail page. Clicks without conversions indicate that the ad is engaging but the vehicle detail page or contact process is not converting.
CTR (Click-Through Rate). The percentage of people who see the ad and click on it. It is calculated as clicks ÷ impressions × 100. In VLA, a healthy CTR ranges between 3% and 8% depending on the segment and the competition. Below 2%, photos or relative pricing may be penalising the ad's visibility and appeal.
CPC (Cost Per Click). The average amount you pay for each click. In the Spanish used-vehicle market, a typical CPC in VLA lies between 0.30 and 1.50 euros. A very high CPC can indicate high competition in that segment or low feed quality.
Conversions. The number of desired actions completed: form submitted, phone call initiated, reservation made. This is the most important metric because it connects advertising spend with real business results.
Conversion rate. The percentage of clicks that result in a conversion. It is calculated as conversions ÷ clicks × 100. A rate below 3-5% usually points to an issue with the vehicle detail page (lack of information, no visible form, poor quality photos) rather than the ad itself.
Cost per conversion (CPL — Cost Per Lead). The average cost of each generated lead. It is calculated as total spend ÷ number of conversions. This is the metric that allows you to compare VLA with other lead acquisition channels.
How to interpret each metric in the context of a dealership
VLA metrics are not meant to be interpreted in isolation: you must cross-reference them to understand what is happening at each stage of the funnel.
High impressions, low clicks (low CTR). The ad is being shown but is not attracting clicks. The most common causes are poor quality photos, a price significantly above the market range for that model, or the ad appearing in irrelevant searches. Solution: review the quality of feed images and verify the price positioning of the vehicles with the most impressions.
High clicks, low conversions (low conversion rate). The ad is engaging but the vehicle detail page does not convert. The most common causes are vehicle details with insufficient information, a contact form that is hard to find or not mobile-friendly, slow page loading times, or the price on the page not matching the ad. Solution: review the user experience on the vehicle detail pages, especially on mobile devices.
Very high CPC. This can indicate high competition in that segment or low feed relevance for the searches triggering the ad. Solution: review the quality and completeness of the feed and assess if there are vehicle segments with lower competition where you can focus your budget.
Very high cost per lead. If the CPL significantly exceeds the cost of a lead on standard portals, the campaign is not being efficient. Solution: identify at which stage efficiency is being lost (impressions, clicks, or conversions) and take action on that specific stage.
Signs that the campaign needs adjustment
You shouldn't wait for the data to turn negative before taking action. These signs indicate that something needs reviewing:
The cost per lead rises continuously for two consecutive weeks. This can indicate that competition has increased in that period (other campaigns in the area) or that the feed quality has deteriorated (outdated photos, expired prices).
The conversion rate drops without any change in investment. This generally signals an issue on the vehicle detail page: a change in web design, a broken form, or vehicles that are no longer available but remain in the feed, generating clicks with no possibility of conversion.
Impressions drop significantly with no budget reduction. This can indicate that the feed has few new vehicles (the algorithm learns better with dynamic and varied stock) or that Google has detected errors in the feed during validation.
The learning phase does not end. If after four weeks the campaign still displays the "learning" alert in Google Ads, the volume of conversions is insufficient for the algorithm to optimise. Solution: lower the conversion threshold (using micro-conversions like visits to the contact page) or increase the daily budget.
To improve the quality of vehicle detail pages that receive clicks, you can review our guide on how to make your cars stand out on portals.
Where to find the data: Google Ads, Merchant Center and Analytics
Google Ads is the main dashboard to manage and measure the campaign. Metrics for impressions, clicks, CTR, CPC, conversions and cost per conversion are available in the campaigns dashboard. The "Search terms" report (although limited in Performance Max) provides insights into the searches triggering the ads.
Google Merchant Center shows the status of the feed: how many vehicles are approved, how many have validation errors, and what those errors are. A feed with many disapproved vehicles reduces campaign reach. Checking feed errors weekly and correcting them is part of basic campaign maintenance.
To keep your feed always updated and avoid errors in Merchant Center, you can consult our guide on how to sync your dealership's stock with Google VLA.
Google Analytics 4 complements Google Ads data by adding details about post-click user behaviour: how long they spend on the vehicle detail page, what percentage scrolls down to the form, what percentage leaves without interacting. For this data to be useful, the dealership's website must have GA4 installed and conversion events configured correctly.
How often to review and what to do in each review
Weekly review (10-15 minutes). Verify that the campaign is active, that daily spend is in line with the planned budget, and that the cost per lead hasn't experienced sharp changes. Check Merchant Center for new errors in the feed.
Biweekly review (30 minutes). Analyse the evolution of primary metrics (CTR, conversion rate, CPL) compared to the previous two weeks. Identify vehicles with the most clicks and verify that their detail pages are working correctly. Update prices in the feed if there are cars that have changed prices on portals.
Monthly review (1 hour). Compare the cost per lead of VLA against the cost per lead of traditional portals. Evaluate if the budget distribution between campaigns (if there is more than one) is optimal. Decide whether to scale up investment or adjust the strategy for the following month.
If you want to delve deeper into how to integrate these metrics with your other business performance indicators, you can consult our guide on essential KPIs for used-car dealerships.
The metric that matters most: cost per lead vs cost per sale
Cost per lead is the most common indicator used to evaluate VLA performance, but the most relevant one for overall investment decisions is the cost per sale: how much advertising cost you to close each sale.
If a VLA lead costs €5 and the lead-to-sale conversion rate is 20%, the cost per sale is €25. If a lead from Coches.net costs €12 but the conversion rate is 15%, the cost per sale is €80. In this scenario, VLA is more efficient even query-wise if its CPL might be lower than the CPC of portals.
To calculate the cost per sale you need to track where each lead that ended in a sale came from. Without that tracking, you can only compare CPL between channels, which is a valid but incomplete indicator.
If you want to understand how to connect investment in VLA with your dealership's complete digital strategy, you can download our free Google VLA guide for dealerships.
Over 750 dealerships already use Dealcar to manage their daily operations
Dealcar integrates Google Vehicle Ads data with dealership stock and operations, allowing you to calculate cost per lead and cost per sale by channel automatically. With this visibility available without extra manual work, decisions on how much to invest in VLA and when to scale are made with real data.
If you want to see how it works, you can book a free demo at dealcar.io.
Frequently Asked Questions
How many conversions do I need per month for the algorithm to work well?
Google recommends a minimum of 30-50 conversions per month for Performance Max to optimise effectively. If you do not reach that volume with form conversions, you can add micro-conversions (visits to web page contact, clicks on phone numbers) to give more signals to the algorithm, although their informative value might be lower.
How do I know if the issue is in the ad or on the vehicle detail page?
If the CTR is normal but the conversion rate is low, the issue is on the page (after the click). If the CTR is low, the issue is with the ad or the vehicle price (before the click). This distinction determines what needs to be fixed.
Is it normal for the cost per lead to vary significantly from week to week?
Yes, especially during the first few weeks of the campaign (learning period). Once the algorithm stabilises (normally from the third or fourth week onwards), week-on-week variations should decrease. Sharp shifts after that period usually indicate changes in competition or feed quality.
Is conversion data on Google Ads reliable?
It is reliable if conversions are set up correctly. A common mistake is counting visits to the form thank-you page as conversions without verifying that the form was actually submitted. For more precise data, cross-reference Google Ads data with leads registered in your CRM or management system.
Index
Why measuring is part of the job, not an option
The essential metrics of a VLA campaign
How to interpret each metric in the context of a dealership
Signs that the campaign needs adjustment
Where to find the data: Google Ads, Merchant Center and Analytics
How often to review and what to do in each review
The metric that matters most: cost per lead vs cost per sale
Frequently Asked Questions
Why measuring is part of the job, not an option
A Google Vehicle Ads campaign that is not measured could be performing well or poorly: without data, there is no way of knowing. But even more importantly, without measurement there is no way to improve it. The Performance Max algorithm that manages VLAs learns and optimises over time, but only if it receives clear conversion signals: which clicks ended in a lead, which ones didn't, which vehicle detail pages convert best and which ones cause visitors to bounce.
A dealership that measures has three concrete advantages. First, it can identify if the budget is generating leads at a reasonable cost or if there is an issue somewhere in the funnel. Second, it can scale investment with confidence once the data confirms it works. Third, it can detect and correct issues before they consume budget for weeks without results.
To understand the full context of how VLAs work before diving deep into the metrics, you can review the complete guide to Google Vehicle Ads for dealerships.
The essential metrics of a VLA campaign
Impressions. How many times your ad has been shown. A low number of impressions indicates that your budget is too limited, that the feed has too few vehicles, or that relevant searches in your area have low volume.
Clicks. How many times someone has clicked on your ad to reach the vehicle detail page. Clicks without conversions indicate that the ad is engaging but the vehicle detail page or contact process is not converting.
CTR (Click-Through Rate). The percentage of people who see the ad and click on it. It is calculated as clicks ÷ impressions × 100. In VLA, a healthy CTR ranges between 3% and 8% depending on the segment and the competition. Below 2%, photos or relative pricing may be penalising the ad's visibility and appeal.
CPC (Cost Per Click). The average amount you pay for each click. In the Spanish used-vehicle market, a typical CPC in VLA lies between 0.30 and 1.50 euros. A very high CPC can indicate high competition in that segment or low feed quality.
Conversions. The number of desired actions completed: form submitted, phone call initiated, reservation made. This is the most important metric because it connects advertising spend with real business results.
Conversion rate. The percentage of clicks that result in a conversion. It is calculated as conversions ÷ clicks × 100. A rate below 3-5% usually points to an issue with the vehicle detail page (lack of information, no visible form, poor quality photos) rather than the ad itself.
Cost per conversion (CPL — Cost Per Lead). The average cost of each generated lead. It is calculated as total spend ÷ number of conversions. This is the metric that allows you to compare VLA with other lead acquisition channels.
How to interpret each metric in the context of a dealership
VLA metrics are not meant to be interpreted in isolation: you must cross-reference them to understand what is happening at each stage of the funnel.
High impressions, low clicks (low CTR). The ad is being shown but is not attracting clicks. The most common causes are poor quality photos, a price significantly above the market range for that model, or the ad appearing in irrelevant searches. Solution: review the quality of feed images and verify the price positioning of the vehicles with the most impressions.
High clicks, low conversions (low conversion rate). The ad is engaging but the vehicle detail page does not convert. The most common causes are vehicle details with insufficient information, a contact form that is hard to find or not mobile-friendly, slow page loading times, or the price on the page not matching the ad. Solution: review the user experience on the vehicle detail pages, especially on mobile devices.
Very high CPC. This can indicate high competition in that segment or low feed relevance for the searches triggering the ad. Solution: review the quality and completeness of the feed and assess if there are vehicle segments with lower competition where you can focus your budget.
Very high cost per lead. If the CPL significantly exceeds the cost of a lead on standard portals, the campaign is not being efficient. Solution: identify at which stage efficiency is being lost (impressions, clicks, or conversions) and take action on that specific stage.
Signs that the campaign needs adjustment
You shouldn't wait for the data to turn negative before taking action. These signs indicate that something needs reviewing:
The cost per lead rises continuously for two consecutive weeks. This can indicate that competition has increased in that period (other campaigns in the area) or that the feed quality has deteriorated (outdated photos, expired prices).
The conversion rate drops without any change in investment. This generally signals an issue on the vehicle detail page: a change in web design, a broken form, or vehicles that are no longer available but remain in the feed, generating clicks with no possibility of conversion.
Impressions drop significantly with no budget reduction. This can indicate that the feed has few new vehicles (the algorithm learns better with dynamic and varied stock) or that Google has detected errors in the feed during validation.
The learning phase does not end. If after four weeks the campaign still displays the "learning" alert in Google Ads, the volume of conversions is insufficient for the algorithm to optimise. Solution: lower the conversion threshold (using micro-conversions like visits to the contact page) or increase the daily budget.
To improve the quality of vehicle detail pages that receive clicks, you can review our guide on how to make your cars stand out on portals.
Where to find the data: Google Ads, Merchant Center and Analytics
Google Ads is the main dashboard to manage and measure the campaign. Metrics for impressions, clicks, CTR, CPC, conversions and cost per conversion are available in the campaigns dashboard. The "Search terms" report (although limited in Performance Max) provides insights into the searches triggering the ads.
Google Merchant Center shows the status of the feed: how many vehicles are approved, how many have validation errors, and what those errors are. A feed with many disapproved vehicles reduces campaign reach. Checking feed errors weekly and correcting them is part of basic campaign maintenance.
To keep your feed always updated and avoid errors in Merchant Center, you can consult our guide on how to sync your dealership's stock with Google VLA.
Google Analytics 4 complements Google Ads data by adding details about post-click user behaviour: how long they spend on the vehicle detail page, what percentage scrolls down to the form, what percentage leaves without interacting. For this data to be useful, the dealership's website must have GA4 installed and conversion events configured correctly.
How often to review and what to do in each review
Weekly review (10-15 minutes). Verify that the campaign is active, that daily spend is in line with the planned budget, and that the cost per lead hasn't experienced sharp changes. Check Merchant Center for new errors in the feed.
Biweekly review (30 minutes). Analyse the evolution of primary metrics (CTR, conversion rate, CPL) compared to the previous two weeks. Identify vehicles with the most clicks and verify that their detail pages are working correctly. Update prices in the feed if there are cars that have changed prices on portals.
Monthly review (1 hour). Compare the cost per lead of VLA against the cost per lead of traditional portals. Evaluate if the budget distribution between campaigns (if there is more than one) is optimal. Decide whether to scale up investment or adjust the strategy for the following month.
If you want to delve deeper into how to integrate these metrics with your other business performance indicators, you can consult our guide on essential KPIs for used-car dealerships.
The metric that matters most: cost per lead vs cost per sale
Cost per lead is the most common indicator used to evaluate VLA performance, but the most relevant one for overall investment decisions is the cost per sale: how much advertising cost you to close each sale.
If a VLA lead costs €5 and the lead-to-sale conversion rate is 20%, the cost per sale is €25. If a lead from Coches.net costs €12 but the conversion rate is 15%, the cost per sale is €80. In this scenario, VLA is more efficient even query-wise if its CPL might be lower than the CPC of portals.
To calculate the cost per sale you need to track where each lead that ended in a sale came from. Without that tracking, you can only compare CPL between channels, which is a valid but incomplete indicator.
If you want to understand how to connect investment in VLA with your dealership's complete digital strategy, you can download our free Google VLA guide for dealerships.
Over 750 dealerships already use Dealcar to manage their daily operations
Dealcar integrates Google Vehicle Ads data with dealership stock and operations, allowing you to calculate cost per lead and cost per sale by channel automatically. With this visibility available without extra manual work, decisions on how much to invest in VLA and when to scale are made with real data.
If you want to see how it works, you can book a free demo at dealcar.io.
Frequently Asked Questions
How many conversions do I need per month for the algorithm to work well?
Google recommends a minimum of 30-50 conversions per month for Performance Max to optimise effectively. If you do not reach that volume with form conversions, you can add micro-conversions (visits to web page contact, clicks on phone numbers) to give more signals to the algorithm, although their informative value might be lower.
How do I know if the issue is in the ad or on the vehicle detail page?
If the CTR is normal but the conversion rate is low, the issue is on the page (after the click). If the CTR is low, the issue is with the ad or the vehicle price (before the click). This distinction determines what needs to be fixed.
Is it normal for the cost per lead to vary significantly from week to week?
Yes, especially during the first few weeks of the campaign (learning period). Once the algorithm stabilises (normally from the third or fourth week onwards), week-on-week variations should decrease. Sharp shifts after that period usually indicate changes in competition or feed quality.
Is conversion data on Google Ads reliable?
It is reliable if conversions are set up correctly. A common mistake is counting visits to the form thank-you page as conversions without verifying that the form was actually submitted. For more precise data, cross-reference Google Ads data with leads registered in your CRM or management system.
