Box lots or pre- filled large pastic bags is one of the best methods I have seen. As for price... use your judgment on the "good" stuff. I attended an estate sale of a quilter and the "good" stuff was selling for $3.50- $4.00 yard on the first day . The second day all fabric was 1/2 price. If you have a sign indicated the second day of the sale that fabric is 1/2 off on the second day... you will get your premium price on the first but probably clear it all out on the second.