I used to buy what I liked,usually a yd or 2.That's how I ended up with a whole lot of different types & is also how I have used stash for well over a year.
Recently bought 4yds of basic white to use in a quilt.Fabric in LQS is around $11.50 a yd.Too rich for me.....but it saves me money,cause I stay out of them & do my shopping on line.:o

If I "like it" I buy a yard and a half. If I "love it" I buy three yards.

I love scrappy quilts so I buy 1-2 yd cuts. I buy 3 1/2 for wide backs and 3 yds for borders. I've got more fabric than I will ever use, but that does not stop me. Then the pillowcases happened and I'm buying 2 yds for them.