Here we go again;> A guy with a screwdriver can call himself a repairman and probably does an adequate job. But, unless he's had certification from authorized manufacturers, this type of service can void any warranties. I had my old Morse serviced for $69. It's non-computerized and since it's close to 50 years old, no warranty to worry about. I'm not about to let a guy with a screwdriver near my new 830 Bernina. Off to the dealer, and yes, higher cost it goes.
Just like a person with a shovel can call himself a landscaper...not.
I don't pinch pennies on my expensive, important equipment. Sometimes I think people here only care about pennies and not quality.