They’ll generally accept a cashier’s check. Ours would also accept a personal one as long as you didn’t mind them delaying mailing the title for a few weeks.

I made a down payment on a car with a money order and the dealer yelled at me that the agreement said they weren't allowed. Eventually they relented, because they wanted to complete the deal.

Back in the 90s, I tried to pay for a computer with a certified check and CompUSA treated it as a likely counterfeit.

That’s crazy. I’ve never had that problem, even when buying cars out of state. Were you paying the full amount by check or something?

Yes, was attempting to pay full amount. Couldn't remember my PIN to unfreeze my credit, and just seemed like it would be easier since I was in a position to pay in full.

That makes somewhat more sense. Trading a signed title without a lien for a check places a lot of risk on the dealer. Although there are ways to mitigate this, maybe the dealer in your case didn’t feel like bothering or it didn’t occur to them.