According to a post from the National Real Estate Investor, occupied U.S. rental units rose 20% above the prior 10-year period. Investors have flocked toward multifamily as a variety of economic factors have pushed more and more would-be buyers toward a life of renting.

One of the great things about multifamily rentals is that the steady stream of cashflow adjusts annually along with inflation... and with good options available to outsource property management, investing has become easier than ever.

"The homeownership rate across all ages is near historic lows. For-sale housing may recover, but a full return to the prior peak homeownership rate is not anticipated. Apartment living is generally a more manageable expense and flexible living arrangement than a single-family home. It is now cheaper to rent than buy in more than half of all counties nationwide." - nreionline.com

Millennials in particular have struggled to nudge their way into homeownership as student loan debt has now reached $1.5 trillion (and growing). The reality is that with a negative average net worth among most younger millennials, a decent credit score and the debt-to-income ratio has become hard to come to buy.

"first-time buyers dropped from 39% of all sales down to 30%" - nrei

The more renters there are flooding the market (and staying there) the safer the investment. Cost of living being one of the most significant challenges cities face in the U.S. Currently, 24% of renter households in the country spend more than 50% of their annual income on housing. U.S. Dept of Housing and Urban Development categorizes anyone over 30% to be "cost-burdened" ... indicating that they're likely to stay put as renters.