Your question requires a complicated answer.Some quilters might buy a top to finish, but the rub is,by the time they pay you & shipping....there's still batting,backing,thread to buy,binding to cut,quilting to do & binding to finish.
Most quilters paying for a top would expect it to be squared,seams pressed,thread cuts.
On the other hand, nothing ventured,nothing gained.Try selling a few tops in classifieds.I'd go with kids quilts to start,making some you can use if not sold.Good luck.
PS... might see a lot of ppl selling quilts or quilty things to support their habit of buying fabrics :-D