Wow...what a trip you have planned! You are going in a low travel time (except for Florida which is probably high tourist season due to it being warmer weather). What kind of meals are we talking? Are you a steak and potatoes type of person or a sandwich kind of person? I would recommend perhaps eating a large breakfast (which some hotels/hostels provide) skipping lunch and eating an average dinner with snacks thrown in. I lived off of $20 a day by going to the local grocery market and fixing myself my own sandwiches/chips/drinks rather than eating at the local take out food place. On Greyhound you won't have much time to grab much either so take plenty of snacks for the ride. Amtrak has a food car, but they tend to be pricy! What kind of attractions are you wanting to see? Please put Monument Valley and Grand Canyon somewhere in your agenda. You can catch a tour bus from Las Vegas. Personally I would skip Los Angeles and do San Diego instead, but if you want the touristy stuff as a first time thing then go for it. I prefer San Diego for its gorgeous sites and gorgeous people. (Then again I spent 10 years there and am very partial to it). You probably will not need advance reservations for the time you are going, but you may want to check to see if the internet price to book online is cheaper that buying in person. Sometimes it can be up to $10 off per person. Also that means you don't have to locked into a date or time if something should happen. Happy Trails..and have an awesome time!
Ah monument valley and the canyon are at the forefront of the trip cant wait. Also San Diego sounds very good i think i will visit for the day when in LA if possibe. Thanks a lot for your info highly appreciated.