My Guild has a person to person sale every year. What I prefer to purchase is yardage with the amount and price on each piece. I have only purchased handmade precuts once, it was a jelly roll of bright batiks. If you make your own precuts, I would keep them in themes. Batiks, 30's ect. I would prefer uneven ends. Just because, I never know when that little bit of extra will come in handy. As for scraps, I don't purchase them. I have too many of my own. Though I have seen new quilters purchase bundles in ziploc bags.