When you take the Jefferson exit from the highway, you’ll take a left at the light to get to 700 Jefferson. Once past the hotel entrance on your right you’ll see a ramp going up that says rental cars only. You can drive up that to what floor your picking up the car. Don’t worry about driving onto the rental car floors, the car dropping you off will be able to get out. For example if your picking up from budget rental car, you’ll drive up the ramp to the 4th floor, once on the floor drive all the way to the side of the garage closest to the airport. You’ll need to take the elevator back down to the 3rd to access the rental car counters located through the hallway.