Whats this ps3 bundle worth.?

I have a person that might sell me his ps3 slim 250gb with call of duty modern warfare one. Call of duty modern warfare two. Skate two game. Grand theft auto four. Infamous. He wants two hundred fifty dollars for the system. I am thinking that might be a little high for a used system. What do you guys think could I get a better deal or should I offer him less because for a whole 50 bucks more I could get a ps3 slim 160gb console. But what should I do with this bundle. Whats a good price to pay for his stuff.