I have done a few quilt for commission but not many. I have a contract that allows for me to have plenty of time to finish a project and allows for emergency scenarios. I am not the best by any means but I can do a good job on a quilt and do fairly good FMQ on my Grace frame, which is now down. I have not done one in years now for all the reasons you mention. I was able to make a fair wage at the time. With the customer supplying all the materials, batting and backing and I can finish a quilt. If commissioned to make the entire quilt the price is by the block.
I don't plan on doing any more commissioned quilts in the near future