Hindsight is definitely 20/20, isn't it. I'm sorry for your predicament!
There have been so many conversations here on the Board about this subject that I admit to being surprised when someone else has been burned. Most of us advise at least THREE 'absolute' rules:
ALWAYS get a written contract.
Always get a deposit for the fabric/supplies.
Always charge appropriately for YOURSELF - even if you lose the job.
I recently read the best comment about this last one that I've ever heard...."Prices define the quilting clients I get. If I set my prices too low, I will have to work with some low quality clients.”
Jan in VA