How to Evaluate Whether Your Dealership's Marketing Vendors Are Performing

Every vendor has a good explanation for why performance is down. Google Ads agencies blame seasonality and inventory shortage. Aggregators blame algorithm changes and market softening. Social agencies blame iOS privacy updates. You’re left trying to evaluate claims you don’t have the context to challenge, which is exactly where every vendor wants you.

The problem isn’t that your vendors are dishonest. It’s that each one is optimizing for their own metrics, reporting from their own system, and defining success in ways that protect their contract. Those metrics are not your metrics.

The Structural Problem With Vendor Accountability

Every marketing vendor operates with information asymmetry as a structural advantage. They know their platform far better than you do. They control the narrative in the reporting they send. And their definition of success (impressions, leads, ROAS) almost never maps cleanly to your definition: sold units.

This isn’t a character flaw in individual vendors. It’s how the industry works. The fix is not finding better vendors. The fix is closing the information gap with better questions, better data access, and a clearer definition of success that everyone agrees on before the contract starts.

The Data You Need Before Any Vendor Review

Walking into a vendor review without the right data is how you end up leaving with a slide deck and no answers. Before any review meeting, pull:

From your CRM: Leads received from that channel over the review period, contact rate (how many your BDC actually reached), and opportunities created.

From your DMS: Sold units attributed to that channel over the same period. This is the number that almost never appears in a vendor’s report.

From the ad platform directly: Spend, impressions, clicks, and whatever conversion events the vendor is tracking. Not from the vendor’s reporting portal. From the source platform. Discrepancies happen.

From GA4: Sessions from that source, average engagement time, and any conversion events tied to the channel.

When those four sources are in the same room, most vendor performance conversations get significantly shorter.

Five Red Flags in Vendor Reporting

1. The report leads with impressions and clicks.

Impressions and clicks are activity metrics. They measure whether your ads are showing and whether people are interacting with them. They don’t measure what you’re paying for, which is leads that turn into sold units.

Any vendor that leads a review with impression counts is either not measuring what matters or hoping you won’t notice the difference. Ask them to start the next review with leads, then cost per lead, then cost per sold unit.

2. “Leads” in the vendor report don’t match leads in your CRM.

This is the most common gap, and the largest. Vendors count every form submission, chat interaction, phone call, and sometimes even site visit as a “lead” if their platform touched it. Your CRM counts contacts your BDC actually worked.

The delta between vendor-reported leads and CRM-matched leads is usually 40–70%. The vendor isn’t necessarily wrong about their number. They’re just measuring a different thing. The question is which number you’re paying for.

3. ROAS as the primary success metric.

Return on ad spend looks like a performance metric. For dealerships, it usually isn’t.

Google Ads ROAS in a dealership account is almost always calculated using micro-conversions (phone calls, form submits, direction requests) assigned inflated dollar values by the agency. A “3:1 ROAS” could mean the agency modeled $150,000 in revenue based on assumptions that have no connection to your DMS.

Ask what specific conversion actions are included in the ROAS calculation and what dollar values are assigned to each. The answers will tell you whether the metric means anything.

4. Market-wide excuses without market benchmarks.

“Sales are down industry-wide” is a legitimate explanation for lower performance, but only if they can show you the market data. Useful benchmarks: NADA regional data, Cox Automotive retail sales by region, or R.L. Polk registration data. If your vendor is citing headwinds without providing actual benchmark data, they’re asking you to accept a claim without evidence.

5. Budget increases as the primary optimization recommendation.

A vendor that responds to underperformance by asking for more budget is optimizing for their margin. Real optimization (restructuring campaigns, tightening audience targeting, improving landing pages) sometimes means spending less while getting more. A vendor who only ever recommends adding spend is not working on your outcomes.

Vendor Performance Scorecard

Use this framework quarterly for each vendor:

The top three metrics require your data, not the vendor’s. That’s intentional. Any vendor who won’t provide at least view-level direct access to their platform so you can verify their numbers is not accountable to your outcomes.

Running a Real Vendor Review

Most vendor reviews are presentations. The vendor talks, you listen, you leave with a deck.

A real review runs differently.

Open with your numbers, not theirs. Start with what your CRM and DMS show for the period: leads received from this channel, contact rate, opportunities, and sold units. Ask the vendor to explain any gap between their reported numbers and yours.

Ask the five questions directly. How many units did this channel contribute last month? What was the cost per sold unit? What changed this month versus last, and what are you doing about it? What does good performance look like for this channel in this market, and are we there? What would you change if this were your own money?

Require data for any market-level claim. Seasonality, algorithm changes, and inventory softness are real factors. They’re also the default explanation for every underperforming vendor. Specific data backing a market claim is not optional.

When to Fix vs. When to Fire

Not every underperforming vendor relationship should end. Some should be renegotiated, restructured, or brought in-house. The question is whether the underperformance is structural or execution-level.

Fix it if: The channel has real potential for your market, the vendor is willing to be measured on cost per sold unit, and the underperformance traces to specific execution issues (wrong keywords, bad creative, weak landing pages) that are being addressed.

Fire it if: The vendor won’t provide direct platform access, refuses to be measured on your DMS data, or has underperformed for two or more consecutive quarters with explanations but no improvement.

Most dealerships keep underperforming vendors too long because switching feels complicated and the monthly retainer feels like a sunk cost. It isn’t a sunk cost. It’s an ongoing cost you can stop paying. If you’ve fired two or more agencies and the problem keeps recurring, the issue may be structural. See the fractional CMO vs. agency comparison for a breakdown of when each model makes sense. For dealers who want this analysis done once, comprehensively, the Digital Audit is how to build a real accountability baseline before the next vendor conversation.

Frequently Asked Questions

How do I get my vendors to give me direct platform access?

Ask for it in writing as a condition of any new contract. For existing contracts, frame it as a standard transparency request: “We want to verify your reporting directly from the platform.” Any vendor who refuses is protecting information they don’t want you to see.

What should I do if my vendor’s lead numbers don’t match my CRM?

Calculate the gap percentage and ask them to explain it. A 20–30% gap is explainable through attribution differences. A 50–70% gap means the vendor is counting something fundamentally different as a lead. That conversation leads to either a change in how they report or a change in vendor.

How many vendors should a dealership be working with?

More vendors means more management overhead and more information asymmetry. Most groups with 1–4 rooftops should run 3–5 paid channels maximum, each with a vendor relationship they can actively manage. The instinct to diversify across six or seven channels typically results in underperforming everywhere rather than winning anywhere.

What’s the first metric to ask for in any vendor review?

Cost per sold unit from your DMS. If they can’t produce that number, or won’t, that’s your answer about what they’re actually optimizing for.