If the 90's is 1990's it's one thing. If 1890's try to convince them not to refinish. One of the rules of antiques or at least used to be, is that original finishes and patina sell for much more better - they really do, especially for the really good items. i.e. - if I wanted something nice and shiny, I could go down to World Market or Home Goods or Ikea and pick something up. My first refinish job was a big round oak table for my parents. Back in the 70's there was a craze in this "fake" grain painting stuff. Basically a kit with thick paint that showed brush marks and then glazed. If the table is from 1890's or by real "old school" Amish - the finish is likely shellac and can be refreshed rather easily with steel wool and some sort of solvent even dna. If some more modern finishes - stripper is needed as well as a well-ventilated area and lots of elbow grease. Used to be people around that would dip the pieces. Faster and cheaper than hand stripping and would handle stain better, but could also dissolve the glue in the joints and sometimes you had to address those issues also. Likely there is a stain under varnish of some type. I've had stained objects come out real splotchy after stripping - my kitchen cabinets being one thing - so they got repainted!