So some good news for you: provided you’re out of contract with your carrier, they have to by law unlock your phone upon request. I just went through this with T-Mobile as a matter of fact and while it was mildly a PITA it took about an hour of futzing on the phone with a rep and then another 24hrs before the phone was actually unlocked and able to use a local TELCEL SIM card in Mexico. For T-Mobile check your eligibility and follow the instructions here. I can confirm it does work but is indeed annoying in terms of the hamster maze you have to run to make it happen.
