DH has just bought a 2nd hand Toyota from the main dealer in our city. They were happy to accept a credit card payment for much more than the figure you mention. I anticipated they might charge a % fee for credit card payments, but they didn’t.
I think most main dealerships would happily accept credit card payments, but they WILL NOT accept cash – this is due to their responsibilities under money laundering regulations.
Small independent second-hand car dealers will all be different so check in advance, but do also ask if they charge a fee. The banks will charge the dealers somewhere between 2.5 to 5% for credit card transactions, so smaller dealers might pass that charge on to you.