Several years ago I had the "thrill" of going to a wholesale fabric warehouse with a friend who was purchasing some fabric for a local quilt shop's block of the month. The cost was 1/2 of what they were selling it for. So, if it cost $2.50 per yard, then the quilt shop sold it for $5.00 per yard. I think that the bolts had about 10 or 15 yards on them that she got.
HTH