CarGurus, AutoTrader, Cars.com and the rest each send you leads and a dashboard to prove it. Neither tells you the one thing that matters: which one actually sold cars. Here's how to find out.
The short answer: you can't judge a lead source by the number of leads it sends or what it charges per lead. You judge it by tracing its leads all the way to delivered gross, then dividing that by what you paid. Every listing site can be worth it or worthless for a given store — the only way to know yours is to measure it on your own numbers. This guide is deliberately neutral: no provider is the villain, and the good ones welcome being measured.
Cost-per-lead is the metric everyone quotes because it's the one everyone can see. It also hides the three things that decide profit:
Stop comparing cost-per-lead. Compare cost-per-sale and return on gross per source:
| Metric | How to read it |
|---|---|
| Leads | Volume only — the start of the question, never the answer |
| Cost per lead (CPL) | What the vendor charges — useful only next to close rate |
| Close rate by source | What share of that source's leads become delivered deals |
| Cost per sale | Total spend ÷ delivered deals from that source — the real cost |
| Return on gross | Total delivered gross from that source ÷ total spend — the real verdict |
The reason most stores never do this is that the answer lives in two systems that don't talk: the lead is in your CRM, the sale is in your DMS, and nothing automatically connects them. The work is joining them:
Do that and the ranking often surprises people: the source with the loudest dashboard isn't always the one paying the bills, and a quiet source can turn out to be the most profitable in the store.
So is CarGurus or AutoTrader worth it? For some stores, absolutely; for others, not at current spend. There is no universal answer — only your cost-per-sale and return on gross, measured on your own delivered deals.
Why not trust the provider's report? Because it can only see its own activity. It can't see which of its leads bought, at what gross, or which were duplicates. That view only exists inside your CRM and DMS, joined together.
Isn't this too much work to do every month? By hand, yes — which is why most stores don't. The matching from lead to delivered gross is exactly the kind of thing that should run automatically, so the answer is a live number, not a quarterly fire drill.
Each lead stamped with its true origin, duplicates collapsed, and every sale matched back to the source that created it — so you see real cost-per-sale and return on gross per channel, live.