I am now doing a lot of flying out of Dulles (IAD). Have always ubered there but I have never parked there. I went online and saw that I could reserve in advance a particular lot but for this upcoming weekend only economy was available to reserve. One of my employees tells me he never reserves in advance and always gets a spot in the closest garage. My questions to you are:

• Are reservations really necessary for the garages or terminal lot?
• How long does it take to get from the economy lot to the terminal?