I would expect that parts and service to be the bread and butter for any dealer operation. Honestly, unless you are located in the center of a major metro area close to some great roads, I have no idea how you could make it as a single line BMW marquee dealership. Remember, a high volume BMW dealer sells around 150 units per year (there are a couple exceptions, but 150 is the norm for a large volume dealership). When you consider just pure operating costs for a dealer to be in the range of $30,000 per month (building, utilities, salaries) and the fact that you have to pay for your inventory (assuming 10 bikes on the floor at any given time at $18000 apiece, meaning you have $180,000 in inventory sitting there), I doubt there are many dealers who are becoming filthy rich.
As for the labor rates, I've found that BMW labor rates are no more (or less) expensive than those at Yamaha, Suzuki, Honda, or Harley Davidson. Labor rates are market driven, and are not uniquely high for BMW.
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