CAJUN ACCORDION DISCUSSION GROUP
20% of that is Tax... making it around $1900 USD. Depends on the mechanisms and the quality of the reeds, tone and playability as to what it is worth. A Castagnari is around the same price. I would think the box on Elderly's site is worth $850. Be wary of Elderly's descriptions. I have had three unfortunate experiences with their used accordeons.. all because of incorrect descriptions.
It looks like it is on consignment, so I guess they are using the sellers description.
The description is typical of Elderly with some obvious input from the seller.