But you still have to provide (and maintain) a kitchen, a bathroom, HVAC (well maybe just heat), a water heater.

This deal that you mentioned sounds at first blush that it's dead in the water because of the large deposit.

3 hot water heaters, 3 furnaces, etc.3.

When you install them clicked together, that creates the seam that water can and will penetrate.Tile it.

We charge a water or electricity fee.

The attorneys for the buyer and the title insurance company apparently did not do their work because they did not find this debt before closing but they found a stupid lien on my house for a water softener.

I think there may be a market for a lower density campground that offers a higher level of privacy per site with amenities (electric/water hookups, RV dump site, bathhouses, etc...) but...

before you go down the rabbit hole to far as @Bruce Lynn mentioned see if the jurisdiction were the lots are located will even allow a surface operation within their zoning code or that lot size.. thats the first thing I would do.Being an old land man I have dealt with a ton of mineral and water rights.. there is a lot to those buggers..

Look for views, seclusion, walkout basement potential, water feature potential- people love ponds, add trees, add boulders, multiple access or roadside properties, no zoning in Texas counties, check city zoning, location location, utility access.5.  

I hired a GC to manage the build out, but there has been no consensus on who is responsible for the utility payments (Water and Energy).