There seems to be a lot of disagreement about the cheapest place to book car rentals. Like with flights, there’s no magic sauce. You may have heard about Marseille Airport car hire because it is well known. It's the best place to start with. For instance, an acquaintance recently booked a two-week, one-way car rental for $30/day from Boston to Austin on a Costco membership, for about $400 total for the entire rental. It seems expensive but it's actually a great deal