When Kara Koloji went through a breakup six years ago, she had to move out and get a place of her own.

The new place was smaller, so small that she didn't have room for all of her stuff, and she didn't want to get rid of it.

So she decided to rent a storage unit.

Mainly, things I stored were books, kitchenware.

I have a lot of clothes and gear, you could say.

So winter clothes or summer clothes or snowboards.

As people and my family started moving out of their homes, I started inheriting a lot of, you know, knickknacks, heirlooms, which I just didn't have room for.

Koloji isn't alone in her quest for more space.

It's estimated that one in five Americans rents a storage unit.

High housing costs, urbanization, and rampant consumerism

have made self-storage into an estimated $45 billion industry in the U.S. alone.

And real estate investors are clamoring for a piece of the action.

Self-storage has become sexy because people have recognized what a strong fundamental

business it is. Americans love their stuff and they don't want to get rid of it.

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

I'm Zachary Crockett.

Today, storage units.

The modern self-storage industry traces its roots back to the 1960s.

The earliest facilities were more about investing in land

than building a viable business. It began with folks who have good vision, and they imagined where

population was going. That's Anne-Marie de Costa. She's a consultant who's been in the self-storage

industry for 22 years.

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