If you are wanting a v. cheap garage nearby to ever get work done on it consider the guy on sky edge avenue (last house on the right down near City road with the double garage and paved off frontage he works in). He runs an E30 325 himself and seems to have taken a lot of care with it over the 4 years I've seen him own it.
Can imaging him being a very much cash in hand dude, but he seems nice enough when Ive spoken to him and when you see all the immigrants in the area line up to get work done by him he certainly gets good word of mouth.
Edit: hes given me a couple of free bits and bobs in the past so doesnt come across as money grabbing, although that could be as I live on the same road.