Ebay's advanced search feature allows you to search completed listings for what things actually brought. Local markets vary significantly, so you may want to do some window shopping in your area. Here in Florida, quilts are seen as a craft, not art, and priced accordingly. Other places I have lived, the mix was different. It's not an easy way to make a living, but if you can get supplies reasonably priced, you probably can make some pin money anywhere you live.
I went to a craft fair Sunday where two vendors were selling Asian knockoffs with flimsy cloth, barely basted together. Queen size quilts were priced at $200, and I saw no takers. One of the dealers kept trying to tell me it was made of American materials, contrary to what the tags read, maybe to see if I was a sucker.