The iPhone SE is on sale at Best Buy through a monthly payment plan with AT&T/Verizon/Sprint. The plans vary, but the final cost is $240/$290 for the phone and then there is tax and an activation fee. I know for AT&T you could immediately upgrade your device and then pay it off over the phone/online if you so choose and I imagine Verizon and Sprint have the same policies, but cannot verify that. For reference the phones retail for $400/$450 for 16/64GB.
AT&T 16GB/64GB
http://www.bestbuy.com/site/apple…Id=5005
http://www.bestbuy.com/site/apple…Id=5005
Verizon 16GB/64GB
http://www.bestbuy.com/site/apple…Id=5005
http://www.bestbuy.com/site/apple…Id=5005
Sprint 16GB/64GB
http://www.bestbuy.com/site/apple…Id=5005
http://www.bestbuy.com/site/apple-iphone-se-64gb-space-gray-sprint/5005625.p?skuId=5005625