Best thing to do is go there. You cant really get a price over the phone without them looking at it and testing it.
Sometimes you can get an idea of the trade-in amount by checking GameStop's website. Trade ins at Game Exchange will usually give you a little bit more however if it's something that GameStop won't take you won't see it. Game Exchange usually takes everything. They will give you more for trading than cash and you can always call them. They're very helpful with giving you the amount for that day over the phone, for the trade-in. Amounts can change daily.
Very complex question, you'd have to ask an employee who works there.
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