We have not done a video on that topic. Primarily because we're not very good at budgets. But, also, because most of our stays (when were filming a location) are business expenses and we sometimes spend more on a location than we normally would if we were not running a youtube channel.
Prices for RV parks, campgrounds, state parks, etc vary greatly and there are lots of choices if you're willing to stay farther away from prime locations in prime season, or go places offseason. Staying longer and getting weekly or monthly rates can help too. There are also a ton of free camping on BLM (Beaurou of Land Management) land, and the like, if you're willing to boondock (no hookups).
When we started out (and hadn't launched our channel), we wanted to keep our nightly average around $35, that average including everything from $120 a night to free. Our first year, that turned out to be closer to $43. That's just RV Parks and such and does not include fuel, maintenance, etc.
That said, here are some things to consider about full-time RV expenses...
There are also ways to stay free and even get paid at some places as camp hosts. These require varying degrees of work and stay durations, but it can take expenses to almost zero if you're willing to work within those parameters. We've made friends with people who jump from gig to gig and save a lot of money in the process.
In regards to travel expenses like fuel and maintenance, those can be variable also by just staying longer in each place and not moving as often.
Our point in all of this is that expenses vary greatly depending on the style of travel and camping you do.