How much will a sprint plan be for iPhone 4?

My sister and I wanted to buy 2 iPhones with a sprint plan. We went to a sprint store and asked questions but we forgot to ask how much everything will be.
He said the plan would cost around $180 but I wanted to know like do I have to buy the iPhones plus the plan? How much would that be?
How much is the iPhone 4? (We don't want the iPhone 5)
How much will the bill be per month?

The iphone 4 is proably free but you need a plan. A plan depends on your choice of how much data you will be using. Go online and check they will have all the answers. I also recommend at&t. It will be 2 iphones for $2.00 and monthly would be around 130 for both of u!