Unlock iphone 5s never activated internationally?

I'm planning to buy an iphone 5s locked to sprint or AT&T on ebay. And I also wanna use it in my home country. Is that possible to unlock it before activating and then using it with any carrier in US or any other country in the world?

Yes you can. IPhone 5s locked to sprint - can only be internationally unlocked unless using a gpp sim card to unlock it for US. But from doing research now. There are people and website online that can now factory unlock sprint iphones.

AT&T is easiest way to go.

but if both phones has a bad imei only way to unlock those are through a gpp sim card.