My longarm quilter gets .0150 ( one and one half cent) and up per square inch. Multiply the length by the width, that the square inches in your quilt. Then multiply that by .0150 and that's the average cost. Add in 6.00 for thread, and extra if she supplies batting plus tax. I recently had a queen quilted and it cost me 150.00 with batting. My king was 199.00 without batting. But that's average for anywhere around here.