As has been suggested, you should check out the other thread which discusses these issues at length. To cut right to the chase, however, dealers may try to limit the amount you can charge or they could charge you a transaction fee if you let them. But according to their contracts with MC/VISA, they cannot, and if you complain to your card company, they will let you charge the whole cost on the card and will not charge a fee or other penalty for using your card. Naturally, you'll want to negotiate your best deal first before telling them you are putting the whole thing on a CC.