Buy an unlocked one in the other country?
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In other countries you can get a 64gb iphone 5 for free on a 2 year contract, with reasonable and affordable monthly rates. You pay a lot if you exit early, but you can unlock the phone at any time with a simple phone call. You are contractually bound to make the monthly payments, even if you lose the phone, sell it, use it on a different carrier etc. The telco gets their revenue stream (or a lump sum if you break contract), and your liberties aren't squashed. I don't see how simply unlocking the phone can (justifiably) affect cost.
Im not a US resident, so it doesnt affect me, but it is an interesting case study of how powerful the big US companies are.