So I put up my 32GB 4S for sale on craigslist and already have a few buyers interested ($280). I wish to know what steps I need to take to securely erase my data and sell my phone. I've read about restoring, and resetting all through settings > general but is there anything else I should know? Also, I'm eligible for an upgrade already but I'm going to wait to see if they announce anything new. Do I have to talk with AT&T about anything? Like, do I have to deactivate my phone through them? I'm going to be iPhone-less most likely for over a month (going to use an old cingular phone I have in the meantime) and I don't want any issues activating my new phone once and if I get it.