The donor wanting an appraisal needs to contact an antique dealer who actively sells the type of items the donor gave you to get an appraisal. If you explain that (1) you are not qualified because your museum doesn’t regularly buy and sell and the market changes almost daily, and (2) that the IRS frowns on appraisals provided by museums since the museum has a conflict of interest as the receiver of the goods, the donor will probably understand. You can provide a list of area antique dealers and appraisers with their specialties if you want to and have that information.
