i don't know about that shop you mentioned, but what you also have to realize is that they didn't quote you for a USED Power steering pump. They quoted you for a NEW one. You found a used one for 150 and that is good for you, but if you went to BMW and bought a NEW pump, then you wouldn't have bought it for $150. I checked RealOem and it states that your pump costs 530+core USD...and since we know that prices in canada are alot higher than what the US prices are, it does not seem unreasonable to be quoted around a grand for that part installed. Now can a better price be done for a new pump, of course, but if you owned a business and someone walked in the door for the first time and had no loyalty to your business, would you be inclined to give them a discount??? Probably not.
Your making it sound that they are charging you 1000 for a used part that you bought for 150, which is not the case. As for their tactics, well, that is just bad business.
I'm just a crazy m*thrf*cker, livin it up, not givin a f*ck, living life in the fast lane