I buy my batting by the roll fromLady Sew and Sew, they sometimes have deals, and its cheaper to buy a roll at a time. I also save all my scraps and join them together using a wide zig zag stitch. Check out sales for cotton sheets also super king size quilt covers. The quilt covers when split open give you enough backing for two large quilts. Also some of the UK online shops have 108"wide backing, register on the onlibe shops and they'll email you sales and special offers.