when I used to make quilts for sale I charged $15/square foot.
now the only quilts I make to sell are large crib quilts and I charge $50-$75 depending on the amount of trouble; occasionally $100 if I've had to buy specific fabric.
I have a vast stash, my guess would be 5-600 yards, probably more. And, unless I have to use a fabric I hate to part with, I don't charge for fabric.