One of my mentors is one of the largest privately held owner/operators in the US and am familiar with his criteria. 

Quote from @Cam Schwartz: Hi Elizabeth, two reputable GCs in my network focused on the greater Chicago area are (i) Real Restoration and (ii) Construction Cycle.

Many of our clients that are looking at STR are also looking at MTR as Charlotte is currently top 20 in the country for traveling medical professional demand (furnishedfinders), and we are currently one of the largest cities without a medical educational institution. 

At my largest property, rent due dates stagger, because they are set to be on the day the tenant moved in, rather than all at the beginning of the month.

One said only 2 of the largest 100 cities was it initially cheaper to purchase than to rent.  

It can eliminate or reduce the largest expense most of us have.

They are one of the largest REIAs in the county I believe.

I'll split this post into two parts based on your question...NUMBER 1: OBTAINING POSITIVE CASH FLOWIt comes down to many factors, but a few key factors that I have found that have the largest impact on the property's cash flow are below (The below generally holds true for any market.

Even if California will not relent on adjusting emission control standards, and the more than 1,000 supplemental workers at the Stellantis Toledo Jeep plant who are expected to rise to full-time permanent status are laid off, on balance, local incomes are rising.For the vast majority of individuals, a home is the largest single investment of a lifetime.

@Nick RutkowskiI remember looking at McDonald's balance sheet back in college and they are the largest or one of the largest owners or real estate in the world.