This will require waterproofing the basement, moving some piping, adding a doorway, moving heating and water heater.

Taxes, Insurance, water/sewer will be $10k.

My mortgage, utilities (shared), maintenance reserves, and water would be $1,000 per month. 

I've also worked at most construction trades (no high steel) and my share of rehabs.Many levels of USA government are responsible for laws pertaining to land and its usage.

A HELOC on your residence can be a useful tool in real estate but I would certainly be cautious about using that up since that is what could keep your head above water in a financial crisis in either your personal or REI lives.Play out some "what if" scenarios. ie, What if someone loses their job?

I've read before on here about having a plumber come out to do a pressure test on the water/gas lines and electricians bringing out generators to test electrical.

@Dakota Evans no hoa or water fees?

A tenant recently let me know that they observed an oddly high water bill. 

A well designed solar system is designed to offset 100% of your usage based on previous 12 months' usage and conversation about future usage such as intent to buy an electric car, etc.A relatively small bill with the utility will always be there as there is a connection fee for the privilege of being attached to the grid.

@Ernes Sahic while you can certainly get lists surrounding pre-forclosures, short sales, probate, Evictions, Loan Mods, Tax Sales, Divorces, Hospital Liens, Code Violations, Appointment of Substitute Trustee, mechanics liens....I mean you can even get a list of people who had their water shut off....but I don't think there's any service out there that will provide a list based on if the property is a 2-4 unit property.