Since we are into year 8 of fulltiming, I feel that I might have a comment or two that are pertinent.
First, the best place to learn about Fulltiming would be to spend some time on the
Escapees forum - - more fulltimers there than anywhere else and the company was started by former fulltimers.
Second, while there are those who will tell you that you can fulltime on $1500 a month, please believe me when I say that that is subsistence living at best, just one break down or illness away from disaster. An income of $2500 will give one more of a cushion, provide health insurance is available at a reasonable price. Your spending habits don't change all that much when on the road. If you like to eat out, then you will probably eat out a far share of the time. Entertainment costs, hobby costs, clothing costs, etc., will all stay about the same.
It is true that you don't have mortgage payments, yard maintenance, etc., but it is also true that you still have bills. Depending upon the rig, maintenance and repairs can be a big problem, and without good health insurance an illness can wipe out any savings one might have. Fuel costs are an ongoing expense as is the cost of stays at any park, whether overnight, weekly, or monthly.
National and state parks are not cheaper than private RV parks. And most state parks are booked months in advance for every weekend, so getting into them between Memorial Day and Labor Day is usually not a sound option. Plus most state parks will charge you $5 or more a day for your car if you have a motorhome unless you purchase their annual state pass which can be another $75 or more - - good buy if you are going to be in that state for several weeks, otherwise, not a good buy. And at National Parks the campgrounds may not take the Senior Pass since a lot of the National Parks campgrounds are now run by concessionaires. Our one exception to this is the parks run by the Army Corps of Engineers. We love COE parks and use them whenever we can.
Depending upon your style of travel membership parks can be a good option if you buy a used one. We save thousands of dollars each year but we know that these parks have to be in the areas that we travel and we have to use them.
Barb