Took 2 days after pre-booking to propose a car, not only not in the category asked for but at the highest end of their offer, 3 TIMES more expensive than what was requested, with no other explanation than no other category being available (tough to believe or they are terribly bad at managing their park)... Also airport office does not seem to be willing to pick up your calls... I have been a client at Sixt for years, but NEVER again in Qatar!