I just went through the same thing. Here is a copy and past of a post I made a few days ago OG post
HERE.
I don't think you should sell one unless your ready to pay for it later because with sprint you never know. They didn't see I owed them any either but then I started to get calls from the insurance company about they. Just be careful about it.
OP
"So I just had problems with one of my 6800's keyboards. I went to Sprint they filed a e-ticket and told me my phone would arrive at my house in two days.
Well I got it and was not happy with it cosmetically speaking . Not because it was a refurb but because my broke phone was in better shape. So I CALLED Sprint and told them that it was unacceptable I pay $7 a month just for reasons like this they said they understood and would send me out a new one. This happened three times in about a week and a half. After my fourth/fifth call then they sent me a brand new one in a box with everything that comes with it (first phone was scratched up,second phone bad screen,third ppc brand new). They make good money off me and my wife Im not settling for less than what I wanted but more importantly what I pay for.
This is where you have to be careful. When they sent me the phones they didn't send me any return kits and then wanted to charge me for them. Two of their ppc's at $200 and my broke one that hadn't gotten returned yet was not ok with me. Thats $600.
Obviously they couldn't make the charge stick so then they tried to charge me $500 for the brand new phone they sent me. Also did not sick after I called and complained about it 20 or 30 times over the coarse of a month or more."