It's posted on signs all over and when you get your contract all worked out with whatever company you choose they tell you where to go for you car.
There are two different levels, depending on what your rental company is. The rental car counter should tell you how to get to your car, besides, there are signs showing you which escalator to take to whatever rental company's cars.
Correct the cars could be on different levels and places depending on where they are located.
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