professor Nothing, as I recall. Got notice that the phones were going to be made obsolete and just bring them in and get the newest. Don't recall paying for the ones we traded back either. I'd think we paid something like $19/phone when we 1st got them, years ago.
Used to have problems when we 1st got them....Sprint!! Was a horrible company with horrible service in certain areas, esp. rural. Since TMobile got them, everything is just fine. As far as I need things anyway.