If they do park in non-paved areas of front yard or on the street and code enforcement sends us a notice and a potential fine or environmental court appearance, the tenant has to pay for all costs to satisfy the code issue. 

@Todd Rasmussen, I would also try to get a copy of the current septic plan from the town or state (here in NH the Dept. of Environmental Services has many plans on file) and ask whether, if the system needed to be replaced, it could be replaced with the same type of system.

If everything checks out, then I would get a Phase 1 Environmental Survey done. 

You will, most likely, need an environmental survey. 

Here are a dozen things that can destroy you with a mobile home park:1) Paying too much2) Bad market (small metro population and low home prices)3) Bad location in that market (undesirable part of town that nobody wants to live in)4) Bad infrastructure (failing roads, utility lines, etc.)5) Private water and/or sewer6) Master metered electric and/or gas7) Density too high so you can't fit new homes on the lots8) Mostly 1960s and 1970s homes on the lots, as they will end up getting scrapped as people move out over time9) Low lot rents that make the whole business model not worth the effort (like $99 rents in Mississippi)10) Inability to get or retain traditional financing11) Environmentally contaminated12) City or state permit problemsThe bottom line is that -- if you are going to seriously buy a mobile home park -- you need to educate yourself on this niche.As far as finding mobile home park deals, there are basically four methods used:1) On-line (Mobilehomeparkstore or Loopnet)2) Brokers (over 50% of the 200+ parks we own came from brokers)3) Direct mail to park owners4) Cold-calling park owners

Another more environmentally friendly solution is to provide solar heated water.  

I would also investigate the HVAC system and conduct an environmental report if the assets location is in a high demand area. 

Home inspection is a lot of work and paper work.I am renovating some properties and paid good money to an environmental inspector for asbestos testing.

I've noticed that a lot of the listings already have approved architecture and environmental studies.

Don’t use excavation to avoid any environmental problem in soils.