She should not have charged you more, in fact, she should have refunded you something, and or, better...just not started it. Sometimes you get a better reputation by refusing stuff you can not do than by attempting things you can't.
I wonder if you couldn't take it to a LQS and do the long arm yourself? We have a few places in Orlando that will let you work on something and give you a lesson at the same time....
AND...since I live in Florida, and am making a Calif. King size quilt...I would like you to please PM the ladys name. I wont make it Public, but I wont use her. MY Goodness, Bad service.