I received my sisters old 3G for free since she was given a new 3GS from work. I had it unlocked and jailbroken and was now thinking about selling it to make a few extra bucks and then just buying a new 3G at retail price. However, I'm not exactly sure on a few things.

Would I have to get a new contract for the new phone or could I just put my current SIM card in the new phone and use it, no questions asked? Are there any extra fees I'd have to pay?

Any help is appreciated.

› See More: RE: Selling an iPhone and buying a new one.