How much is a new iPhone 5s without a contract?

So i have a 2 year contract with the iPhone 5. But i want to sell my iPhone 5. If i go to the sprint store and ask them for an iPhone 5s to replace an iPhone 5 how much would it be? Or if i were go to best buy would i just buy and iPhone without a contract? Or do i have to buy a new contract

Like $500-700 dollars I'm trying to get the 5s with a contract but I have no credit at all… I'm freaking out if I might not be able to get it… But if you want to save a pretty Pennie it's better to go with the contract. Hope this helped yo!

Without contract:
16gb - $650
32gb - $750
64gb - $850