People are not usually willing to pay for the number of hours that good hand quilting takes. Longarms are very expensive, so if you want to make money with that you need to do a lot of homework first (find out the demand and the going rate in your area), and probably practice on someone else's machine to see if you really like it. Some people have luck selling quilted items on etsy, or in local craft shows. Good luck in finding your own niche.