Yes, replacement parts and service for German cars is very expensive. I've generally stopped going to the dealer for servicing and have been doing repairs after having dropped $4k for two new catalytic convertors, 4 O2 sensors and labor to install it all.
Your best bet on getting a German car is to get one that is 3-5 years old, with 20-40k on the Odo. It's taken a big hit in depriciation, the new car gremlins have been worked out, and you shouldn't have any major repair items or uber expensive 100k services to worry about. When the odo hits 99k, sell it.
