I think you need to be a bit more specific about your concerns. Your trip does not sound especially long. Currently I have been on the road for a month traveling from NY to Badlands NP, then Yellowstone, now Glacier. Tomorrow I will be leaving for the Olympic NP then traveling slowly down the coast to northern CA, then to the big 5 in Utah, back west to Death Valley in November and then returning east for the end of the year.
Once I visit a dump station, a grocery store, and fill the propane tanks, it is like starting out fresh on day one. Laundry is the only longer term issue. I carry a month's worth of t shirts, underwear and socks. Laundry is always a 2 or 3 hour nuisance no matter how many loads you have to do.
Regarding costs, I find RV travel to be cheap. You can make it as cheap or expensive as you want. Fuel costs can add up when I travel long distances, but I do not drive flat out day after day. Spread out over a long trip or weeks or currently of months, fuel costs are no more than when I commuted to work. I don't bother with discounts or trying to find the cheapest station. A lot of variation is due to State and/or local taxes which are unavoidable.
Aside from fuel my travel costs are minimal. It helps that I have the senior pass for the national parks. I average about $7-10 per night for camping fees. I have solar so I don't need hook ups. On the road I typically stay at Walmart or a truck stop.
Food and eating are other considerations. I am often not around areas with grocery stores so I try to plan ahead. I only cook meals that can be cooked quickly and do not require any fresh ingredients. I also pack my small freezer with precooked meats or perhaps a few frozen hamburger patties.
Again, if you can be more specific you will get better advice and comments.