Normabeth,
If you have the basic understanding of adjusting and using a domestic machine you should be able to learn how to use a mid-arm. There is a learning curve to them, and doing the quilting on a frame is a task as well. I'd say within 6 months of practicing you should be doing a pretty good job of it. You'll have days when the thread will break or the tension will be messed up but you'll get it if you stick with it. I love my Bailey Home Quilter, and think it's a great mid-arm. PM me for more info on them.
Desertdebbe