Hello, this is my 1st post to this forum. I am a full time musician (keyboard player) & am trying to get information on the potential value of an Excelsior Excelsiola Art Van Damme Model 730 accordion from the late 50’s. My father purchased it new and gigged with it every weekend up into the early 70’s when he purchased a Cordovox. I’ve played it a couple of times over the past several years and everything seems to work on it. I’ve searched ebay & the internet and can’t find any information on this particular model. I appreciate any input on this. Thanks!