oh.. I have a good one that I 'lost' money on..
Bought a '73 Fender Jazz off ebay for $2100.. When it arrived home, and I unscrewed the pickguard, I found a hole the size of a MM pickup underneath.
Ouch..
Tried to return it, but in the end it's proven to be a great player. Recently had it fixed up a bit, tried to forget about the $1000 I lost on this deal... It feels great, it sounds great, it records well, but man... $1000 down the drain.
and edit;
Never.. ever.. sell any instrument
Unless you're replacing it with a better copy of itself that is. I'm so happy I never got rid of my fretless Jazz copy.. that thing sounds great; completely different from my Fender fretless, but great in its own right. So yeah. Do not sell. Anything. 
Bought a '73 Fender Jazz off ebay for $2100.. When it arrived home, and I unscrewed the pickguard, I found a hole the size of a MM pickup underneath.
Ouch..
Tried to return it, but in the end it's proven to be a great player. Recently had it fixed up a bit, tried to forget about the $1000 I lost on this deal... It feels great, it sounds great, it records well, but man... $1000 down the drain.
and edit;
Never.. ever.. sell any instrument



And maybe having a bad habit of tinkering or being rather violent with gear. Has led to the premature deaths of many beautiful basses I've owned. 