This notion of "just rent a car" is so stupid and unrealistic. Most rental cars are kind of crap unless you spend a lot, which quickly eats up any savings. The agencies don't reliably honor reservations and don't always have the specific model that you wanted. Getting to and from the rental car agency is a huge hassle and time suck, and then you have to drive it back to your house to pick up the rest of the family and luggage. Who has time for that?