I have a Brother CE4000 that I was lucky enough to find on Craigslist for $50 and it was basically new. The girl had sewn one quilt with it. She called it a quilt, I would have called it a placemat. I think you can get these for around $200 at WM.
Every quilter should have a secondary machine. Personally I don't even think one back up is enough but that's just me. I love to collect machines.