Iphone software does it cost?

i believe i must update this iphone should it expense anything

No no, it is free from apple, only plugin ones cable in itunes, then click ‘update’ also it will down load the IPSW (Iphone firmware) along with install that.It won’t take little money from your own account.

Expect this fit your imagination at majority!

nope.just connect it into a computer and also click replace under advice.=)

No, starting from the 5.x versions (or earlier), it really is free.