i charged and got $250.00 to do a simple 6" block (in the customer's colors) quilt, twin sized. it was pillowcase style and only tied off.
it depends what the traffic will bear and how badly the customer wants the item. it's just so hard to know. but don't set the precedent of selling too cheap. you can always come down in price but not up. how little are you willing to make per hour?