I think that the quality of fabric used at the beginning is something that doesn't need to be addressed. You buy what you can afford... and you use it up. You might not get a stash immediately, but over the course of time, you will. You will also learn what feels nice to the touch, and will discover that some fabric manufacturers are more suitable to your style of quilting than others. That said, you can find good quality material just about anywhere. However, if you can actually count the number of warp and weft lines, you might want to steer clear of it. You will not be happy over the long term with it. You have to remember that this is going to be washed over and over again. And it will probably be dried in the dryer too. Inexpensive fabric doesn't wash and dry as well as the branded stuff, say Moda or Bernartex.
I should also note that you must be sure to use 100% cotton for your quilt tops. Regardless of quality, you want shrinkage to be about the same when you do wash it. I learned that lesson the hard way about 35 years ago when there wasn't the same shrinkage in the blocks. If all you can get is 65% cotton, 35% polyester, go with that the entire quilt. Don't mix it.
I hope this helps.
Anita in Northfield, MN