Hmmmm where did you go in Hamilton?
I've personally used Daines Auto, and they are pretty good.
They show you all the warn out or failed parts to justify work.
Plus they have nice, clean, itemized bills...
Their only knock is the price on parts, but I think they get them from BMW and affiliates.
They try to help out with price, but sometimes you gotta bite the bullet or get your own parts. (That's what I do!)
I think with ALL MECHANICS you need to be specific, and the more you know about you car, the less overhead on headaches you get.
The worst is when your car won't start, it could be various things and may cost you more overall due to troubleshooting...