Most desirable things I’ve seen: over the past couple of years a local for-profit thrift has had two very nice monster receivers (one Technics & the other maybe a Kenwood); both priced well above e-bay.
Highest end thing I’ve bought: Yamaha MX-630 for $60. There was a CX-630 and a T60 also but the pre wasn’t working and I already had a T-80, so I left those for someone else.
Highest list price I’ve bought: Cute little Denon HTIB unit that had a stuck CD tray for $6 and change. Replaced the belt with one salvaged from a trash-bound BPC unit and it works although it’s slightly sticky. Does everything, (CD, DVD, receiver, 2.0 and 5.1 output), but nothing especially well and build quality is rather poor. I was shocked to find it originally listed for $1k.
Priciest audio related thing I’ve seen. My local GW had a pair of NIB Di Vinci tower speakers with a price tag of $500 on each one, along with a slightly condescending note saying to ask the manager if you wanted to look at them and you’d better be serious about buying them. I considered asking to see the manager and advising him/her to google “white van scam”, but it was getting late and the store was busy, so I just shook my head and went on my way.