XBMC4Xbox

So I have a chance to buy an unopened Forza Xbox but how can one really tell if it's unopened. I mean can't a person use a hair drier or something to peal off the sticker? Or maybe the top sticker wasn't there to begin with and then the person re sealed the box. So if I do buy it and want to resell it what do I say not to get in trouble. Yes I would see it before I buy it so I can check it out.

Plus how much is an unopened Xbox worth these days?

Any thoughts thanks.