Tip: Don't trade in your old vehicle at a dealership. If at all possible try to sell your old vehicle yourself so you will get a retail price for your car instead of a trade in wholesale price that the San Diego new car dealership is willing to give you. If the dealership is willing to give you MORE money for your trade than you could get if you sold it in the paper, you are probably paying MORE than you should for the price of the new car.