31: Volkswagen Passat
It goes without saying German cars are expensive to repair, but the Passat is a surprising money pit. Depending on the generation of the Passat you decide to purchase, the car can be expensive (via Autolist).
The most common problems are the transmission failing and oil leaking from the turbocharger on the 2.0T model. As with any German car, repairs on this one are costly, oftentimes more than what the car might actually be worth.