So even if the cash flow is only 3% or 4% cash on cash, that’s enough to provide a protective layer to cover unexpected items.To me, the cash flow is NOT to put spendable cash in my pocket NOW but rather keep the property self supporting while it increases in value over the long term.In addition, every property a purchase has a cash reserve fund - call it my rainy day fund or my Sominex account (ie I can sleep at night knowing if the furnace goes out I have $8,000 in my reserve fund to replace it.)One final note, I have found once one reaches a certain net worth, cash flow no longer is a concern, there is always as much cash flow as anyone wants.Final note, who will have more cash flow someone with $1M investible cash or $3M investible cash?

We would prefer something that allows us to sleep peacefully at night.

Sufficient infrastructure: Companies select locations with major airports, highways, and a large population of potential workers.

If you can hold onto these properties over time (ie cash flow sufficient to not lose money), you have already "won". 

@Jefferey Eutsay I’ve found the BP Calculator to be sufficient for analyzing most of my deals.

With your experience, having sufficient capital to cushion any mistakes is important.

If there was a clear lease violation sufficiently serious and they were given written warnings to correct the issue and did not then you could probably evict.

Keeping yourself not so leveraged helps you sleep, while leveraging enough, helps you retire early! 

They may have zero possessions left or a place to sleep. they cynical side of me says this does stop many well off people from taking the money and running.

That’s simply because they can sleep outside there compared to homeless people in colder climates who must sleep in shelters so they don’t freeze to death.