Iona, I understand where you are coming from. Luckily for me the local quilt shops have 50% off fabric bins, and I freely admit to shopping the sales.
I also use Connecting Threads fabrics and thread. I know some complain about the lint from the thread, but I frequently clean around my bobbin case so it is not an issue.
I am in Canada, so my Big Box fabric store is FabricLand. I used to use some of their novelty prints, but as a person who mostly washes when it comes into the house, I find the fabric is lacking after washing. I have to wash the fabric as I get skin irritation from the chemicals in the fabric.
So now I set an annual budget and when it is gone, I no longer shop, unless it is something needed to complete a project.
I look forward to seeing your project.