The short answer is that it depends on what you buy.
Say you and I each have $100,000 to invest. You buy a single property and pay $100,000 cash. I buy 10 identical properties and put 10% down on each. I get great terms from my lender and my note on each property is $500/month. (I know, I know - just follow me - this is for illustrative purposes only and we're ALSO going to ignore all other expenses for this illustration.)
If these 11 properties rent for $500/month, you make $500/month and I break even (but I'm killing myself managing 10 properties).
BUT - if they rent for $1000/month, you make $1000 and I make $5000 - so I'm starting to feel better about all my hard work. Somewhere between $500 and $1000 is a tipping point.
I know that you asked about a flat market but markets always come back eventually and I can be patient, even at break-even, because the renters are paying the note. If the market appreciates a modest 5% over the next X-years, my equity has increased by $50,000 while yours has increased by only $5000.
All that said, if you can afford to pay cash for resort property in SOWAL, you don't need my advice.