Most of the time I just buy what I think is pretty and reasonably priced. If its really thin and flimsy I pass. If I'm gonna pay 10 big ones for a yard of fabric then it better be the better quality. My mom hasn't sewn in years, and was in shock when she went to the fabric store with me. She said back in her day it was cheaper to make all you clothing and anything else you could sew, but now its cheaper to go buy what you want and need already made. Sad how things change.