Generally, no matter what the sales person says, when the time comes to pay, they will not accept more than $3-5K on a credit card. Eats into the profit margin too much on this kind of transaction.

By the way, have spoken to several new Hummer owners recently. They are not happy campers. That gas tank is BIG. Much more costly to keep full than expected. Of course, Hummers are really cheap now.