Big players like Ford, GM, and even tech companies are betting on Detroit.

That will only leave healthcare to be something I will not have direct ownership or control over as I cannot feasibly own a hospital, nor an insurance company.

How do I research the company?  

He also founded an HVAC company with 110 employees, and also ran several construction companies.

The only other question I would suggest is that you do engage a property management company to review your quad and review your monthly financials.

The company cries the blues about having to inject money into maintaining the trees so they can make a profit.

I do have a silent investor, but when it comes to securing funding, it often feels like I’m navigating it alone.

I'm a local, CT based investor, flipper, and property management company owner.  

Honestly looking at your situation I'm not sure I would recommend you do the taxes yourself,  change of accounting method (F 3115) isn't easy for someone that hadn't done them before these online software companies make things seem easier than what they are, they are good for less complex situations. 

Texas tends to favor landlords in these cases, but follow the legal process exactly—any misstep could delay things.As for protecting against retaliation or property damage, installing security cameras (if you haven’t already) to monitor common areas might be worth it.