Welcome to RTA!

This sounds like quite a trip, but I'm really not sure that you will be able to get by with 0 campsite fees. For one, that freecampsites website has the reputation of lots of errors! Some may even find you looking up at a ranger or law enforcement officer in the middle of the night, being asked to "move on". There are a lot of cheap campsites, but finding them takes time. It means stopping in at the local BLM/forest service office, or a small town police/fire station, and asking. It may mean driving into places on dirt roads. You will need to learn how to cache what foods you DO carry, away from animals. Finally, most of the "free" campsites have nothing there, so somehow, you are going to have to find and carry in your own water to use for cooking, dishes, and personal hygiene.

As far as figuring out your fuel usage, this is how my husband and I budget: We figure out the basic mileage just to get us from place to place. Then we add 20-25% for added mileage (around the national parks, to the grocery store, to another place of interest). Divide by the smallest mpg our vehicle is known to get. Use the fuel cost calculator on this website (look down) and use an average price you expect to pay per gallon for fuel.

The national park annual pass is a great bargain, and if you're planning to do that many parks, you should either pick it up just slightly ahead of time, or at the first park you stop. However, that said, be aware that it won't pay for everything. If you go into a national park with a cave, it won't pay for the tour. It won't cover your parking ($12) at Mt Rushmore. So you'll either have to allow for those costs, or avoid those parks altogether.

You will have to plan a little ahead about your grocery situation. Fishing licenses cost money and every jurisdiction wants a different one. Same with hunting in any form. Stop in a larger city on your way into a touristy area, to avoid paying higher grocery prices. (As much as people put down Walmart, it has a lot more budget-priced items than the grocery store in West Yellowstone.)


Donna