In 2012, a small audience of real estate investors gathered in a conference room in Colorado

to learn about a lucrative opportunity.

We'll be together the next three days.

It's just one goal and estimate everybody here, a competent mobile home park investor.

So we're going to show you how to find properties, negotiate them, renegotiate them, finance them.

That's Frank Rolfe, co-owner of Mobile Home University.

Do due diligence on them.

How to properly buy them, close on them, turn them around, and operate them, and even sell it. It's kind of college-styled, about 30 hours in length, where we teach them everything

from finding mobile home parks to evaluating them and running them.

Eleven years ago, capitalists weren't clamoring to own mobile home parks.

That has changed.

Today, investors are cashing in on one of America's biggest and most vulnerable, affordable,

housing markets.

When I bought Gledhaven, my very first eviction was a veteran who had severe mental problems. Very nice individual, but didn't have their act together in a big way. And hadn't paid rent in months. And I then had to evict her for non-payment.

I had to do something.

For the Freakonomics Radio Network, this is the economics of everyday things.

I'm Zachary Crackett.

Today, mobile home parks.

At the dawn of the automobile industry in the 1920s, trailers were toys for the rich,

a way to travel the country in luxury.

That changed during World War II when the federal government bought tens of thousands of trailers

and used them to create permanent housing communities for factory workers.

...