There's a used Dampp Chaser listed in the local classified ads for $30. Is that weird? It seems kind of weird to me, but you folks know best.

Some people will try to sell anything.

Pwg

I'd buy it in a second! I know some owners that would really like one, but can't afford it.

I think you'd need to be very careful about your legal position, in fitting a second-hand electrical appliance in a user's home.

What if there was a fire?

I'm sure there is a US equivalent, but in the UK, electrical appliances have to pass a PAT (Portable Appliance Test) for electrical safety, before they can be re-sold. This includes items sold in thrift stores/charity depots. They have to have a sticker on them showing when they were tested and passed, which has to be done by a qualified person.

Oh c'mon now David, safety first? Gimme a break! No one would pass off a defective appliance...that might hurt someone. People don't do that around here...

😅🤣😎

Pwg

And if you sold a piano with a dampchaser already installed, would it then make the piano an electrical appliance? Maybe so, in the UK... Anyhoo, I would still do it and not lose a minute of sleep.

The piano would not be classed as a Portable Electrical Appliance, but the DamppChaser bar would, and there would have to be a PAT certificate sticker on the plug top.

http://www.hse.gov.uk/electricity/faq-portable-appliance-testing.htm

The voltage in the UK is heftier, of course, than that in the USA. It's 240V here.