My friend is offering me his 4month old 32gb Iphone 4S (with applecare) currently under ATT for a little under 400 dollars (Is that worth it?). Once I purchase the phone from my friend, do I need to be on a carrier to unlock the Iphone 4S or can I unlock it without being on the ATT network? From what I see so far, it seems like it will cost some money to unlock the phone. I see some people are saying that it cost about 10-50 dollars on ebay to do the unlock. Would I need to pay a price for an unlocked method? If not, what are the safe and free methods in order to unlock the phone?