It is difficult to come up with a price because it depends on what the buyer is willing to pay. I would ask the person who services the machine what a fair price would be.
I lost my motor skill and ability to concentrate after going thru menopause. My eyes are not as sharp as they once were. I was finally diagnosed with Chronic Fatigue Syndrome. I actually gave up quilting for over a year. I can't drive any more so I have to rely on friends. But I discovered if I stick with patterns where the seams don't necessarily have to line up, I started quilting again. It gives me such satisfaction with what I am able to make and helps me fight the depression. PM me if you wish to talk further.