I'm looking to start this with between $75k-$100k (inlcuding $55k down) to account for maintenance ect. 

That is what my lender required.

Tutorials  emphasize the need to do due diligence on all the following:--check for taxes and liens against the property--find out which taxes and liens, if any, will remain attached to the property--make sure it is a buildable lot--to do above, you need to establish how the lot is classified for code purposes, and access the lot specifications, minimums the lot must meet for construction to be allowed--you further need to find out what its sewage situation is because 1) municipalities have different lot minimum specification for lots with public sewage and lots with septic; and 2) if the lot will require the construction of a septic tank, you need to take that into account in your decision.

How we all get around this in the industry is the rest of the states if its a commerical purpose loan no license required..

I was told by my HVAC gut that the government was going to be requiring AC units to be butane based refrigerant replacing R410A so the prices were going up 10-15%. 

This, of course, would require the bank appraises 20% equity on top of what you paid. 

TSAHC does not require borrowers to use an approved REALTOR®, however we provides several resources to help find a REALTOR® familiar with TSAHC’s programs.My lender and I are using TSAHC with investors/buyers for their primary residence.

Do not do work that is not required though.

The big differences are that RV parks are typically amenity rich which requires more overhead, can be seasonal in nature (but not always), require a nearby destination to work well (as opposed to employers), and use values that are typically 2 points higher in cap rate.

Sometimes, sellers might require a smaller down payment or even none at all.