if i can be so bold......you are not ready to give a price.
It does not appear you have all the details and hope you have not given an estimate of $50-$100 You need all the details before even thinking about a cost and then make your estimate and be sure and get it all in writing especially regarding any changes during the process.
There have been some horrow stories here on the Board about making quilts for others. And it makes no difference how much the customer is going to pay for materials. Your labor is a separate issue. I imagine your customer is wanting a finished quilt to be handed to her and not just a top.