Good question.
They check it before you come, but using the wmc it should not pose a problem.
And hey guys, being at the car rental return 2.5 hours before the flight, is not a luxury...
Took me some 10 mins to find the place. Needed to wait about 15 mins so that they accept the car back, and waited 20 mins for the bus. Bus ride is also at least 10 mins.