As long as no “healthcare” services are provided (like medication or personal care), it’s not regulated by the Department of Health.

If you are following the rules then everything should be OK.This is no different than a health inspector visiting a restaurant.

She’s currently not paying rent, and while she has some health issues and no stable income, she’s been communicative and open to general talks, with a possible option to vacate through a cash-for-keys arrangement, though this might take around six weeks and some hard work.I plan to rehab the property and eventually rent it out, potentially to a Section 8 tenant.

Is the property just a regular-style house or something you can build an experience around?  

As they are in their mod to late 70's and in declining health. 

As long as there is no "healthcare" being provided (medicine, baths, etc) then it's not regulated by the department of health.

It's usually best to talk with your neighbors about your plans and get their support as one of the variance tests is that the requested relief does not cause a public health issue or alter the essential character of the neighborhood.Try googling "tests for a variance in [your state]" and talk with your local zoning department.

The months of supply, a key indicator of market health, sat at 8.5 months.

They have regular meet ups.

Unfortunately, my work phone is forwarded to my cell phone as I mainly work from home due to health issues.