SIM unlock a Japanese iPhone?

Just bought a iPhone 5 through a person to find out it is still locked. (yay) Apparently the carrier is soft bank, and so is mine. I put the SIM card from my broken phone into the one I bought to find that it is not valid. So I must get it unlocked. I heard it is expensive and I'm not trying to spend a fortune. I heard about some unlocking websites, but I wonder if any of you guys know how to unlock it at home? If not, what would be the cost to go to a carrier to unlock it?

Sadly, in America and Canada it is $100-$300.
I do not know how much that is in Japan.

  • Will my Japanese iPhone 5s work in the US? 8Unlocking it is not the issue. Its currently locked to AU, but I would take it to get unlocked after I get back. I want to know if there are any hardware differences. My friend told me he thought that US and Japanese iPhones use different antennas or something. I want to know if this is true, or if the iPhone design is standard. Will I be able to connect to a US network with it?
  • Will a straight talk iPhone work in Japan with a Japanese sim card? I'm pretty sure you can put a sim card in it but I was curious I want to go to Japan sometime but it is difficult getting a phone there being a foreigner and it is pretty expensive but I see people switch their sim cards with there phones a lot like with at&t ect. I wonder if that would work the same overseas? Like putting a japanese cell service provider's sim card in the phone? This probably sounds really stupid though but thank you!
  • What sims can be used on a Japanese locked iPhone 4S? I bought a second-hand iPhone 4S which is currently locked to a Japanese sim network but I live in the UK. Can any micro sim work and is there any way to unlock my phone if needed?
  • Renting Japanese SIM Card for 1 Year? I'm going to Japan soon on a student visa and i'll be staying there for about 1 year. I need a japanese phone number that also includes data (i need to receive phone calls from part time too, and tethering for my laptop). I want to bring my iPhone 6 with me and i'm hoping i can use them there. Any tips?