We have a lot of forested dry land.  I thought about doing an RV park here and the cost turned out to be astronomical.  
We are close to power and have city water, but I would have to build the disposal system.  
the initial plan was for only 15 slips. 
For 50 Amp unmetered we were into 30K+ copper.  
Water would be 42K because the township required that we put an hydrant 1000ft from the road (classed as dewllings).  
I got several quotes on an huge septic system and they ranged from 50 to 80k for some variation.
And all this to park coaches for 30 to 40$/night for 4 maybe six months a year.  
Texas might have more year, but it still does not work well for an FHU park. 
Matt