Hmmm, that would depend on the machine and what they consider maintenance.
My old singer not the collectable ones, just an old one for the 60's or so. I could take her apart and figure how to fix her. But still rather than tell me what and easy fix something was I spent $100, cause I didn't know better.
Now I have a much more expensive machine. The store people, always say bring it in. no matter the problem bring it in. Feels like I am wasting my money, too scared and with no back up on how to take her apart and fix simple things.
If it is actually, "here this is how you can fix this" instead of "keep it nice, any problems bring it in" I wold be interested.
Oh and the manual! I aught not get started on the manual!! Trouble shooting, was lame and didn't cover any troubles, no diegrams on the mechanisms, nothing. Just no details at all, would love a behind the curtain, this how you can fix this at home class.