Unlock iPhone from Japan to Kazakhstan Is there any way I can unlock an iPhone 6 in Japan and use it in Kazakhstan?

I heard from reading other forums that it's got to be unlocked, but aside from that how can I be sure it will work back in Kazakhstan? 

Also what are the cons of buying and using in different country?



Following some answers, to clarify

I know where to get an unlocked iPhone 6. I want to use the iPhone 6 in Kazakhstan. The cost of iPhone 6 is expensive in Kazakhstan. Want to buy it in Japan and bring it to Kazakhstan to use. 

I want to make sure the unlocked iPhone 6 I buy in Japan can be used with networks in Kazakhstan, and if there's any disadvantages to this approach as opposed to buying the iphone 6 in Kazakhstan.

Thank you.



update 27/05/2015

found this link: http://www.apple.com/iphone/LTE/ but it doesn't mention Kazakhstan, so not very assuring.
If you buy a mobile phone that is locked to a carrier (as is common practice in the US), then you can only use it on that carrier. If you buy an unlocked mobile phone, then you can use it on any carrier. This is true for all mobile phones, including the iPhone.

It sounds like getting an unlocked iPhone in Japan might be difficult, but other Asian countries only sell phones unlocked, as it is illegal for a carrier to lock them in those countries. (This is certainly the case in Thailand, where I live.)

Hong Kong and Singapore also sell all their iPhones unlocked.

It sounds like you might be better off sourcing a phone from one of those countries. It might be possible to buy an iPhone on the 'grey market' in Japan also, but if you do, make sure that you test that the phone works with SIM cards from two different carriers, and that it is not jailbroken, before you buy it. This is because a jailbroken iPhone can be 'software unlocked' to use with any carrier, but doing an OS update in the future would then return the phone to its previous locked state.

My recommendation is to buy an iPhone from a reputable dealer in a country that does not lock its phones (e.g. Hong Kong). Note that unlocked phones are much more expensive than locked phones.