How much could I get for my PSP and games?

lolz 1st 3DDS is ok :\ just no games currently but fun with games but game stop doesn't take games rlly for alot my brother took (With out my mom permission so he got in trouble) about 50 at least xbox games and came back with a a HUGE receipt but only like 30 buck he took the games for like .50 cents each so like it wont be much of a deal he even gave in new games -_- rip off.