From what I've gathered in the last 3 months of full timing which just happens to be my first 3 months also

is, it depends. Where do you want to go? What kind of "neighbors" do you want? I haven't been to Florida or Arizona yet but I can't imagine it'd be much different. I've paid as much as $64/night (my personal limit) to only paying $115/wk. I've had an awesome corner lot with a huge front yard, porch, bench and fire pit to being so close to my neighbor that awnings can't be put out.
Unexpected expenses I've encountered so far, knock on wood, was just a crazy crazy winter. Which required a heated hose, a hillbilly skirt and a Mr Heater for keeping lines thawed. Oh and I had to replace two breakers because I accidentally overloaded one by plugging in a ice maker to an outlet that happened to run off the same breaker as the electric fireplace. Oops. Easy fix though, just the cost of two new breakers.
I've never had a problem with internet. But again that's a personal preference. I won't stay somewhere I can't use the internet. I have God awful insomnia and need an outlet in the wee hours of the morning. I use my phone to hotspot tv when there's nothing available through my antenna.
Your personal preference of lifestyle will determine your expenses. Just have a good credit card or two for the unexpected and good insurance. You'll be fine.
Start researching rv parks now in areas you want to visit. Google maps is as good as anything.
Happy travels!