As far as I know, CarMax doesn't negotiate on the price. The price they list is the out the door price. So it's not like OP walked in and they added document fe

As far as I know, CarMax doesn't negotiate on the price. The price they list is the out the door price. So it's not like OP walked in and they added document fews and headlight fluid fees. He knew the price he was going to pay for the CarMax car, and was pleasantly surprised with the trade in value of his old car.