From Zurich Airport, Switzerland to Donaueschingen, Germany

We arrived early to try picking up the car. Initially, they told us there were no cars available and asked us to come back at the scheduled time. Later, they informed us that a car was available, and we managed to get it about an hour early. The return time remained the same as in the original booking. We found out later that this extra hour was crucial; otherwise, we would have been charged for an entire extra day! Also, the booked model was not available, so they upgraded us to a different, brand new car with a navigation system.