Unfortunately since your friend is not making these herself, that means she has no idea the amount of work that goes into the making of a quilt. Personally I think $100.00 minimum for each quilt for your labor, with your friend purchasing all the materials. Even at that she is getting a bargain. I am a longarm quilter and occasionally I will be commissioned to make a quilt from the ground up. Now I provide all the materials in these instances but I charge $500.00 for a single or full size and $1000.00 for a queen or king. Of course I am not suggesting you charge those prices, I am a professional with a business, BUT your time, skill, and work are valuable and please don't sell yourself short! Just mt $.02 worth! Let us know how it goes! I once read that if you work for free for your friends because they're your friends, you'll be working for free forever, because your enemies are not going to seek your skills. Think about that.
and blessings to you for being such a sweet friend!