When I was buying and selling antique quilts, I did quite a few repairs, both on my own quilts and others. I had a stash of vintage fabric.
One that comes to mind, an antique log cabin, for a very good client. I thought we had made small piece LC's, with the strips one inch wide - well these strips were about 1/2 that size!! I had to replace quite a few strips, by hand of course. I think I charged her $700 - she was happy to pay it. The quilt actually belonged to her 90 year old mother.
Another time I got a quilt in to wash for a client. It was pansies on a muslin background. When DH saw it after cleaning he thought I had ruined it . The muslin had been so dirty, he thought it had been a brown fabric.
Then there was the time I bought a lovely antique blue and white quilt with a fat lumpy batting and big stitch quilting. I really just wanted the top , to re quilt it. I thought, that will be easy to pull the quilting stitches out. WRONG - every other stitch had been back stitched. Took forever.