Considering your circumstances, the order of my priority would be:
1) Park Model
2) Fifth Wheel
3) Travel Trailer
1) As may slides as possible
2) No slides
Considering where you plan to park the unit, you will need some kind of water source, some kind of electric source, and some kind of sewer or septic tank system / or some way to haul away toilet waste.
In addition, you'll need some way to dispose of solid waste, like trash, cans, paper, bury it, burn it, or trash pick-up.
If you are enslaved to modern technology, you'll need internet access; also possibly cable or internet or satellite television access. And telephone access, be via internet or a cell phone.
Here are some problems: Electric companies, most often, will not just run a line to the middle of nowhere and put a meter on a pole with a plug below it. They require the electricity to go inside an actual building.
Unless there is already city water run on the property, you'll need to have a well dug. This will require electricity to run a pump. At my mother's house, last year, "they" had to dig a new well. It was 200 feet deep (in Indiana, and cost over $15,000). A friend of mine is considering undeveloped property in Colorado. To dig a well at their "dream property" (undeveloped) will cost them over $50,000 ... Fifty Thousand ... yes). Of course, if you have a creek running through the property and you don't mind deer, raccoon, and skunk pee in your water, well... you might save yourself some money there.
Other utilities, like satellite dishes for television and internet, and telephone land lines really want their equipment running into a solid building.
One thing you might consider is building a very solid and good utility building that will satisfy the electric company as a permanent building. It would also give you somewhere to maintain that well, and also some place to run all the other utilities into. You could even install a flush toilet and sink and double up on it's purpose.
I'm not saying it can't be done. You CAN just take a camper out in the middle of no where, park it, and live in it by carting your water in and out, tossing your waste on the ground or into a hole, and have no heat, air conditioning, or lights. You could use Kerosene lamps and flashlights forever if you want. Nothing says you have to have electricity and all the conveniences that go with it. Nothing! It's your life style. Take a bath in the creek, catch your own opossums and fix your own stew like the Beverly Hillbillies. Yes, you can. But I don't think this is the life style you're looking for since you are considering an RV with all the electronics going on in it.
Anyway, it's not impossible, but it's not done as cheaply as you may think.
Good luck. Follow up on this thread someday and let us know how it comes out for you and how you've worked out all the details. What you are proposing to do is really a dream for a lot of us!
Good luck!