Do you really think a rough small time dealer is going to take payment by credit card?
I've not found one yet that wouldn't, although they all grumble about it.
I am clutching at straws a bit, but if you have a better idea...?
Presumably the OP has a receipt for the deposit, which also mentions thenreg number ofnthe vehicle? If so, that puts the seller in a slightly awkward corner. The OP now has a financial interest in the vehicle, effectively a co-owner, so the dealer can't lawfully sell it to another customer. Again though, enforcing that might be more expensive than the cost of losing the deposit. Nevertheless, its an angle.