I concur with the others. I used to "cheap out" and am weaning myself from that. I hand-quilted so a quilt that has $70 worth of materials in it lasted months. Now that I'm machine-quilting, I have stopped using the cheapest materials I can find and am finding that I'm spending about $100/quilt. I do use cheap thread (the polyester regular sewing kind that my local drug store sells for $.30/spool) and cotton everything else. I buy my tops online for $50 or less. I have found a few that I had to have that cost $70. So that's my biggest expense but I can't imagine I could make one any cheaper than that. I used to buy batting at Joanns or Hobby Lobby, but have been getting them at the same time I buy my backing (one big piece) at the fabric discount store. Last time, they cut me exactly how much I needed for the top I brought in. It's queen sized and I spent $60 on the white cotton Warm and Natural batting and backing. I probably could have gotten it cheaper if I'd used my Hobby Lobby coupon, but it's 3 counties west! I have been using spray basting ($6-ish) and I pressed the basted sandwich and it smooshed the batting down good and made it so much easier to quilt on my domestic machine!! I will use up the rest of the poly batting and the acrylic blankets I have for my hand quilting but will splurge on the cotton batting for the machine.
The eye opener for me was when someone gave me some older quilts. I don't know how old they are, but they are applique and the fabric is falling apart. Not the seams or the (hand) quilting, but the fabric itself. Then I looked at the quilt that I'm working on that is made of poly blend sheets and wonder just how long it will last and it makes me sad to think that she will either have to put it up or wait for that "one last time" that she pulls it out of the dryer and finds that first hole....
That having been said, I'm making my 10-year old neice a quilt from a sheet set!