Ok, today I was complaining about how expensive the data plan for my iPhone has been getting when I don't really get 3G everywhere I should. (I am a happy AT&T and Apple customer, I just made a bad decision in buying my iPhone during my current financial struggle.) I've always seen people selling their iPhones on craigslist and eBay for ungodly amounts of money. How do I get in on this? I understand that I need to jailbreak and unlock my iPhone for maximum profit, but I would like to avoid that. Can I cancel my data plan without repercussions? Can I sell it after simply doing a full restore? Any help would be appreciated. (Also, I know I'm a noob but I couldn't find a designated eBay forum. If there is one, mods please move this.) Thanks.