HoD seems to list a bunch of cars that simply aren't there. At each location near me, there's at least a couple of cars that cannot be booked for any period within the next week. But the website will allow you to book those cars two weeks in advance. Like clockwork, those reservations will get moved to a different car a few days or a week before the reservation date. Their system is simply a mess compared to zipcar. I've only had zipcar change a reservation on my once in a year.