Depends on when you're going - usually in spring and late fall, car rental companies want to move their stock from/to north to south. We got a deal with Hertz two years ago in the spring to drive an economy car from Orlando to Buffalo for $5, plus we drove it all week before going home at that rate. This past May, National had a similar deal, although it was $14.99/day. Am hoping for one from North to South this fall (October) as airline prices are ridiculous and so are car rentals, so would love to combine them and just drive a one-way and keep it for the week, then fly home.