For the average accordion player - this should be no problem. Just pick up the accordion and:
1. Pull bellows without playing anything (see how loose the bellows are - LEAKS?)
2. If it has shifts - see if they actually work (both hands)
3. Out Bellows - play every note up the keyboard (for each reed - Low-Middle-Hi etc)
4. In Bellows - play every note down the keyboard (for each reed - Low-Middle-Hi etc)
Listen for notes that gargle, notes that don't sound, and if playing notes with two middle
reed playing - listen for speed of the musette (vibrato)
5. SMELL the bellows for mildew and musty smell
6. LOOK at bellows for tears, rubbing, bellow corners.
7. LOOK at accordion body for scratches, cracks, discolorations, & dents
8. LOOK at case. Handle, latches, dents, rips, etc.
9. Play ALL bass buttons - do they stick? slow to pop back up? Don't sound or gargle
10. Are all the bass button riding even and the right keys nice and level and respond well?
11. LASTLY - shake the accordion and listen for loose reeds rolling around. This was caused by old bees wax or exposure to heat.
If all the above meets your approval - offer 30% less than what the seller is asking. If they BITE - then they are a motivated seller OR a NON-ACCORDIONIST.
Walk away from the accordion if:
1. the bellows are in bad shape (costs $400 to custom fit bellows on Keyboard accordion)
2. ANYTHING wrong with the left hand - very expensive - would have to be shipped to Chicago or New York to be repaired at $75 an hour plus shipping both ways
3. Smells Funky (Shows it was not stored proper - and too costly to replace bellows and all reed leathers and case.
4. TOO many notes don't sound or gargle (cost avg. $15 a NOTE (per reed bank) to tune and $30 a note (per reed bank) to replace a reed)
5. Bad Case - replacement cases for 120 bass full sized accordions start at $250
If you own an accordion that fits the "walk away" criteria - consider having it repaired professionally before you sell it.