I'm buying a factory unlocked iPhone 5 tomorrow from craigslist. I've asked for the ESN and run it through two sites that have said it is clean. I will be bringing my T-Mobile SIM with me tomorrow to pop it in and take the phone for a spin. Any tips? What should I be looking for? What should I test? What sections should I check? I plan on activating while I am there before handing him the money. That means I'll associate my Apple ID with the phone. If I do this can this person still "report it lost or stolen" a week later and have it locked? THANKS IN ADVANCE!