Hi there,
My wife and I drove from Chicago to LA last summer along Route 66 which is not quite all the way east to west but a significant overlap on your journey I guess. Like you we didn't know where to start (we live in Cardiff) so I'll gladly share anything I can.
We hired our car from CarHire. We opted for a 4 door Pontiac G6 which was great for us. We had it for 3 weeks but I can't remember what we paid other than it was the cheapest option. Carhire3000 are a broker and our car was actually from National. When we arrived to pick up our car it was really simple - they told us to literally go out and pick any car from a particular area alone and drive it out as the keys were inside! When asking for a quote by email don't go for the first option as 2 weeks later they'll email you again and will have reduced the price a little. Also, for 3500 miles we paid a little over £200! We didn't have a problem with the one way hire but i remember it being £100 more.
We were able to get breakfast and lunch for about £2/3 per person and finding a diner was never a problem.
If you have any questions on places to stay or sights to see I'll help as much as possible. It's worth checking out Route 66 as a potential run - we had the time of our lives. We opted for sidetrips to vegas and grand canyon then upon reaching LA drove up the west coast to San Fran. If you want a copy of our itinerary just let me know.
Good luck,
Steve
