If I see a whole collection that I love, I will purchase small amounts of each print from 1/4 to 1 yard. Then I will look to see which one of the prints I would use for a border, binding or any other larger part of the quilt and purchase from 2-4 yards. If it is just one fabric that I see and fall in love with I usually purchase 2-3 yards. I have done this when ordering online also. There are a great many fabric stores online who have a half yard minimum but if you ask, most will cut you
1/4-1/3 yard pieces when they know you are taking all of the collection plus some larger pieces.