I do sell my quilts, but not many of them, because I price them below what they are "worth" but enough to make me happy. I always time my work for custom quilts - but that is after I have given a price for the completed project with materials and time estimated, and the price has been accepted. My quilts are scrappy and the scraps come out of my stash for a nominal amount. Borders, sashing, batting and backing are priced out before the price is figured. About 1.5x cost - at least I get to keep the scraps! Then, when the product is shipped, I include an invoice for the remaining amount to be paid- plus shipping costs, as I do insist on a 50% payment to start the project, and the diary of time spent in construction. No one has ever backed out of the purchase when they realize the steal they are getting on the labor.
I do truly love to quilt - it keeps me out of trouble and grounds me. I make beautiful things that I don't have room for in my house. I'm challenged to create something that someone wants and stretch my skills, and learn new things. Those are the reasons I'm comfortable not getting what they are worth on the "real" market. But as I said, it makes me happy.