I have a Bernina, and when I bought it, I was given two years of cleaning for free. Then it was $65 on my third year for service. So I think you were being over charged for cleaning, and next time you do want to get it cleaned, call the other place first. I also have two Singers and the cost of cleaning for them was about the same, but I do drive further to take them to be cleaned. And my old Penney's machine I take to my Bernina place and it's the same cost. As far as how often, it just depends on how much I use the machines. I sew every day, so I do clean and oil them myself a lot in between check ups. $4,000 Bernina, $80 old Penney's it doesn't make any difference, I want them to work, so need to keep them in good working order.