I had to laugh at this, because I just finished hand-quilting a queen sized double wedding ring. The cost to me was sitting from 8 AM in the morning to 9 PM at night and stitching. I did take time to eat and do those type of things. I started after the 3rd Thursday in January and finished yesterday. My mother had the quilt over 1/2 stitched before arthritis made her give it to me for finishing. Her stitches are beautiful, and mine are...well. Oh, another cost was callouses on fingertips...I can’t use a thimble, but the plastic pads worked fairly well. So I had to laugh at thinking about the cost. :-)
I had Amish do a couple of queen sized quilts and was charged by the amount of thread they used. I thought it very reasonable, considering all the work.