It is expensive to sew. I did post the other day under pictures, pillows I had made using a sheet from a thrift store. I got 5 pretty pillows out of one thrifted $.99 sheet. I'm also going to post a picture under pictures of a quilt and it's back that I made a month or so ago. It wasn't from a sheet but I intentionally mismatched the back because I like the backs as interesting as the fronts. I'll label it Baby Quilt with pieced back so you can find it.
You know what else works, telling people you sew and are looking for fabric. I have people give me things all the time. They would rather it get used than sitting somewhere dry rotting. Try it. Good Luck