How much does it cost to buy out a 2-year contract with Sprint?

I am about a year and a half through my contract right now, and my family is going to get the data plan in December. I need to know how much it is to buy out a contract so I can get an Iphone. Thanks!

$349 plus phone price

For me its only 149 a month. Its cheap for me because I got a discount off from my work id. I have unlimited everything and data.

but if you dont use a discount from work or anything like that. Its 349 a month.