How much money do i need for an iphone?

The only way for me to have a phone is to simply buy on for myself and pay my own bill because my parents refuse to. I would like to own an iPhone 5(s) but am not sure how much it will cost for me to just walk into verizon and say "Hi, I'd like an iPhone." I currently have 250 dollars in my bank and have small Saturday Job where I make 40 dollars per week. (160 a month). Would I qualify to be able to successfully buy an iPhone on my own and keep up with the bill? Thanks.

Added (1). I said iphone 5s but i meant just 5.sorry!

The phone will cost $199 for the 16GB phone. Are you already a version customer? If you are, are you up for an upgrade? They will charge you more money to upgrade early.

You probably need to be at least 18 years old to have a cell phone policy since contracts with minors can go void.

In that case, keep out on promotions. Many cell phone carriers offer free phones when you start a policy with them. Then it matters on what type of policy you get. You need to pay for minutes, texting, and data along with premium fees for using a smart phone.

OR

You can get a prepaid plan at something like Walmart. I'm not sure though if they are going to carry the new iphone right away.