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-Midd…