Unless you use a dealership that offers on-site self-financing, there is very little difference between used car dealer financing and new car financing. The key difference is the fact that you are dealing with a used car, rather than a new car. Indeed, used car financing, which still bases its rate on the car you are buying, also is a freer form. In that it can include things such as extended warranties and the like that will help to boost the profit for the dealer. New car financing is pretty much cut and dry where you take the rebates or special programs, and if you like the price, you sign. The basis of any loan, though, is still the value of the vehicle. Any money the dealer chooses to take off is much like the rebates you get on the new car side.