Have a Swap/Trade party. Invite your quilty friends to come with their "out of favor cuts". AND see if you can swap.
Piece your backs. Make a few extra blocks and use them down the center or offset in the backing.
Frequent the Salvation Army,other thrift stores, estate and garage sales. THEY are FULL of good fabric. Goodwill is the only one Ive never found good useable fabric in. And Goodwill has become pricy as well. Salvation Army and Estate sales are your best solutions.
I'm retired and my budget has shrunk big time. BUT I still never use sheets for backing as it has a different weave count. I know many rave about them but I've never found them to be really the best choice.
ASK FOR GIFT CERTICATES to your favorite quilt shops for gift giving times.
I shop sales online too. BUT swapping with friends is really a great way to get some fresh stuff in your home.