Oh... I should have known it was a 3rd gen Max.
The dealer should have provided you with working codes to begin with when he sold you the car. You should ask him for a working code or reset the codes so you can put in your own. If he doesn't, report him to the BBB and let him know that you don't appreciate him trying to con extra money from you. A dealer wouldn't sell you a car and not give you the ignition key, so why should this be any different.
At any rate, I believe if you go to the maxima.org forums and ask the 3rd gen people about a reprogramming procedure, they will probably be able to help you out. There's almost nothing a dealer can do that you can't. Tthe only thing I can think of off hand is checking certain OBDII codes, and if you have a 3rd gen Max, then you have OBDI and its not an issue. (OBD stands for On Board Diagnostics in case you didn't know).