If you are risk adverse real estate, (especially out of state) is not for you.

If there are problems with the existing boundary lines, and the neighbors are encroaching on this property, then this will give the neighbors all of the right in the world to file a legal claim for adverse possession.

(To add to it, he recently had a stroke, and sounds rather adversely effected by that). 

Paying balances off to zero does have adverse affects on your score.

For owner occupied property you have to eject them and then adverse posses property for 3 years to then have the chance to do a quiet title lawsuit.For HOA property, you just call the HOA and ask them how much it would be to make them current.This is what you need to buy and read...http://www.deniselevans.com/Alabama-Tax-Sales.htmlI would be very cautious with these, i learned the hard way that in the end you will probably need a lawyer.

Different strategies, if your risk adverse no debt is a good option but don't expect to have the net worth right away, it takes time to build.Side note: I know of the Ramsey program and have known people who have completed it and where diligent in their self control, wiping out all their debt within a couple years.

@RickHarmon –Rick, thank you so very much for your comments.I know it is true that Adverse Possession cases are extremely rare. 

They all had to deal with adversity, from others (people from the family not believing in their vision) from the business, and also from themselves (self doubt, poor decision) and sometimes from the elements (I am sure people who were n the middle of flipping houses when COVID hit will back that up...); on the positive side, it shows there is not one path to success; The fact you have so many books cited as having an impact in their life and their journey, is a hint but it is also confirmed in their interviews.

If there is any relationship between the former owners and the tenants that is information you'd like to have as well, as you wouldn't want them teaming up against you if you take some adverse action against the former owners.

Holding real estate delays the adverse conditions but it also effects earnings since the real estate held is a non-earning asset, which is of more concern than the number at the bottom of the balance sheet.