1) Yes, absolutely. Fortunately for you this was a local deal and you demonstrated the pice worked fine before the sale.
2) I would aid him in getting it in for warranty if I was the holder of the warranty and the unit was still covered, but in a case like this, it likely won't be covered by warranty (depends on the company). Otherwise, no. He broke it, he's on the hook for the repair, FWIW you are probably right abouth the fuse/trip circuit in amps, I don't know about CDP's having them though....so it could be more than you think.
2) I would aid him in getting it in for warranty if I was the holder of the warranty and the unit was still covered, but in a case like this, it likely won't be covered by warranty (depends on the company). Otherwise, no. He broke it, he's on the hook for the repair, FWIW you are probably right abouth the fuse/trip circuit in amps, I don't know about CDP's having them though....so it could be more than you think.