Hi guys, I need some quick help, like really quick help! I'm about to purchase an iPhone 5S used. The owner says he got it new from a local retailer. He has the box, receipt, and all included accessories. Apparently he has a 5 and would rather sell the 5S for cash. According to him, it's never been used. The box has been opened, but it's still in plastic (as well as the accessories). Apparently the phone was locked, so he only opened the box to unlock it before he sells it. Apparently he used an online company to do an "IMEI"-unlock. I have no idea what this means, but he claims that it's now fully unlocked and works with all networks. Question 1: Is the phone fully unlocked from the operator as well as Apples activation servers? There is no risk of me buying a "brick"? There is no risk of the carrier once again "locking" the device now after its been IMEI unlocked? Question 2: Other than asking for the receipt, and checking the serial number, how do I make sure it's not stolen? Also, should I ask to keep the original receipt when I buy the phone, so that I can take it to Apple and use the 1 year limited warranty in case something goes wrong? Reaaallly quick replies are greatly appreciated!