One thing that I should mention is that since you DO NOT want a new vehicle to tow, watch the weather. On one of our trips, in Albuquerque, we picked up an 11 month old Chevy HHR, with less than 10,000 miles, that had suffered very MINOR hail damage. You really have to be close to the vehicle to see the dents. It was a previous Enterprise Rental car.
In any case, the vehicle had all of the remaining warranty, came fully equipped and detailed, had a sticker of close to $25,000, and we got it for $8500, out the door.
While in town we had a base plate installed at a shop and sold our Saturn to a local dealer. I always carry my titles with me.
Most areas in the country do have hail storms from time to time and if you contact the rental companies after a storm, you may be able to get a great deal.
By the way, small shallow dents like we had on our HHR can be removed with dry ice and heat, as long as there is no crease in the metal. :B