Building an RV park for overnighters?

I would think that a mobile home park may be more lucrative than an RV park. You have year-round use, more predictable income, and less manpower to keep it running. There's no dump station needed, no showerhouse, perhaps even no office needed. There might be some affordable housing state aid programs available to help develop it in some cases.

At least here in Vermont, the design and permitting for a sewage system for a campground would start to approach an extensive investment in itself, to mention nothing of its installation. It would likely be simpler if municipal sewer is available and had sufficient capacity.