Ditto candyquilting. Start out small and decide if you like the way the project looks. You'll know as you grow in quilting about how much to buy etec.
I don't like to buy anything with pinked edges. After you have been at this game a bit, you'll have plenty of fabric to strip into whatever sizes you need.
A gal named Bonnie Hunter has a method of scrap management that I use. I cut leftover scraps into 2.5", 3.5", 5" in strips and blocks to use in other quilts. At some point you'll have a huge stash.