How much will I have to pay for Iphone 4s?

I know I will have to pay a deposit because I have no credit history, but will I have to pay the deposit fee and the full price of the phone or just the $99 2-year contract price+deposit fee, I have a debit card and I'm 20 btw, any answers or input would be appreciated

Get a droid. You will be MUCH happier in the long run. Much more customizable.
BTW: Go through Wirefly online. You typically get a better deal on your choice of carrier.

You've to pay the deposit and contract price.