So I got an upgrade AT&T iPhone 4s for my wife and before she opened it she looked at mine and didnt like it. So I was looking to sell the brand new, never opened still in package iPhone 4s. I bought it a couple of weeks ago so I assume it has the newest firmware on it. Looking at eBay or craigslist. My question is: what do I need to do to make sure I'm protected and the person I sell it can use the phone? Do I open it and take the sim card out? Do I activate it and then take the sim card out? Or do I just leave it unopened? I have sold iPhones before and just took the sim card out and had no issues, but I wanted to make sure there wasn't a better way. Any help would be greatly appreciated. Thanks.