selling quilts is one of those things---it takes time to be anywhere near consistant...you may sell 2 or 3 quilts in a week-then not sell another one for 6 months...unless you have a shop, a following (even the well known-famous quilters make their income from their books, awards, patterns, shops...and occassionally from the sale of a quilt)
i sell alot of quilts- but i also go weeks/months without selling any quilts- i shudder at the thought of having to depend on that to pay my bills. generally i keep track of materials- and time- then decide what the quilt is (worth). to double or triple the cost of materials, then add in quilting, then add in your time...you would be looking at thousands of $$ per quilt- even a baby quilt would be in the $300-$400 range...not very realistic for most of us...unless we have a (following) with a demand for our work (like the famous ones- and they have spent many years reaching the point of having that following.)
often i make quilts for someone then show them off--and someone will ask if they can buy it.
ive had quilts on the 'quilts for sale' website that have been there for over a year- then suddenly sold