In theory, what you say is correct, but my limited experience with Japanese mechanics is that they're cheaper.
Now I usually purchase new, while under warranty and return them once it's expired to avoid maintenance costs.
However, the costs of new parts from the dealer appear much higher with German cars, but since my cars are new, you may be correct.
Somebody once advised to get no closer to repairing my own vehicle than One Hundred Dollar Bill. Two left thumbs or something like that.
Archaea,from the deep dark blue leagues beneath the Sea. Cool under pressure yet a microbe in the sun.