Most people have no idea what it costs to make a quilt. Spend some time and jot down what the materials cost for you to make a couple different type of quilts you have made and how much time it took to make them. Take these costs (figuring in a decent hourly wage for yourself and not forgetting the 'house' costs - power, tools) add in what a local LA costs and then you have a very base cost. When you submit this to the person asking, they may change their mind very quickly. If they are serious, have them go with you and pay for the materials themselves and then get a deposit for the remaining costs BEFORE you start. Also, be very honest about the time it will take you to complete it. Handle it like a professional would handle it - you are contracting for a job.