I want to buy this camera from a friend, it has a lot of hours on it so the heads are worn out. What would be a fair price for this camera?

I want to buy this camera from a friend,

Check E-Bay prices, especially recently completed sales, then deduct a bit for known condition (maybe $500???).

Keep in mind that the XL1s is a bit long in the tooth and approaching the end of factory service availability before long.

Do not expect much, if you do, it cam put friendship at some risk.

Dear Steve,

What indications do you have that the heads are worn out?

Find out the total cost for head replacement and add that to the sale price and see how it compares.

I second Dan's question. I thought mine were shot, the cleaning tape wasn't doing its thing. I was about to send it in, but lent it to a friend with the caveat that he would have to let the tape roll a little first to get past the broken timecode problems I was having. He went out and got a little off brand cleaning tape (I had a sony or something, he got a zynex one) and ran it before the shoot (I told him it would help, but not solve the problems). It solved the problem. On the off chance, I ran it in the little JVC camera I was using as a deck and had written off as a usable camera and it restored it to full functionality.