Where does a sellers responsibility stop?


I have a ethics question that I need some input about. I just sold my pre amp to a buyer who made a local pickup. The pre has always worked flawlessly. He demoed it and then we took it out of my system. I started to remove the top to take out the tubes and pack them as they were when I purchased the unit. He said not to bother and so we packed it in all the original boxes.
He called me 3 hours later and said that the pre amp doesn't turn on. I told him that it had never had a problem like that before but, he was welcome to return it. He seemed really miffed at me like I cheated him. Now the problem is, I will be refunding his money but, how will I know that he didn't drop or short out or whatever the unit ?
Did my responsibility stop once it left the door?
agaffer
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I would take it back provided it still worked in your system & was in the same condition as before. If there are any signs of abuse I would refuse the refund but maybe like in Budrew's situation, the guy didn't know how to hook it up. Then again maybe it's tube related & that gets into a gray area.

If everything's OK you won't have any problem reselling if it's the LS5 because you can reverse the SOLD on the ad.
If he came to your house and demo'ed it and then he took it with him, I would say your responsibility ended at the front door. It worked fine until it was out of your sight.

It would be different if you had shipped it to him. Then it is your responsibility until he confirms it works at his house.

I think you are being more than generous in taking it back.

Those are my two cents worth anyway.
Thanks for all your responses. He brought it back and I took a close look at it and could see no sign of abuse. Audio Research is notorious for having the toggle on/off switch go out through constant use. I'm betting that it was just bad luck and it happened after he took it home. He still wanted the unit, so, we agreed that I would keep half the money until it was repaired, which I would bear the responsibility for, and then he would return to pick it up.
That seemed like a fair compromise. This way if the repairs show abuse I use the money he left to pay for it and return the rest making him responsible. If the dealer sees it as a non-abuse repair situation I pay for all the repair and still sell him the pre-amp. I think in dealing with used equipment you always should treat the other party the way you would want to be treated, even if they are obnoxious.
Welcome him to the land of tubes. What did he expect?
The reliability of solid state?
I brought home my Rocket 88 (with all tubes removed).
I re-installed them carefully & watched one of the EL34s turn frosty white on start-up. I replaced both tubes w/a matched set & moved on.....

This gentleman probably does not have any experience w/tubes...