How much would they give me if I gave them the god of war saga collection in perfect condition?

I'd say about $10-$30. Some of their games are in that price range. It depends on the condition and console of the game.

Ive never sold anything to them so im not sure how that works yet

Well,thanks for the advice

Not much. I took in a brand new in box transformer that is worth 250 dollars and they offered me 49. Then they turn around and resell it for almost triple.

Its comparable to gamestop to be honest, and its probably less than you think

Less then half price