As I've stated elsewhere, I purchased a device-only Verizon iPhone 5s that I'm using on AT&T. However, I have a relative with a Verizon iPhone 5. Next year, if I sold it to him, would it be as simple as popping in the SIM from the Verizon iPhone 5, or would he need to take it into a store and register the IMEI to his account, since obviously it isn't registered to any Verizon account right now.