Probably not the advice your looking for, but I'll give it anyway since I've been down this road. 

You have to save all of your rental income to build up an emergency fund.For me I have a one-page application and we check credit and criminal record.

Specifically wondering if it is part of the East Mountain Road 

The City has told me that the sign has been scheduled to be removed and that they will not allow any new signage on the road.

I want to provide the best rentals I can for my tenants and hopefully that will translate to happy tenants that will help me build some wealth down the road.  

To me the quadplex would be dual purpose, while you are not living there it serves as a reliable stream of income, once you move there, you could live in 1 of the units while you build your permanent home, and you could also use it for when your family comes over for large gatherings.A 2nd option might be to build an RV park, Unless their are zoning restrictions, you should be able to build one fairly inexpensive, with a septic system and either public water or a well, you can keep your costs to a minimum by doing gravel roads, which are easier to remove later if you don't want them. 

No I’m not sure what took you down that road but just as stated they would stay at a property you own that’s for rent maybe that explains it better  

Although you can't look up criminal history, you can get landlord references from other landlords with whom they have worked.

In other words, over the course of time the business owner will hits bumps in the road where they lose money.  

I'm hoping to build out 10-15 spots for mobile homes and another 8-10 for RVs in another part of the road frontage (I have two roads).