The billionaire entrepreneur and former Shark Tank star revealed he snagged a $25 million estate at a jaw-dropping 50% discount, a deal he says exemplifies one of his core investing principles.

Cuban reflected on the purchase in a 2022 interview with GQ. During his days at MicroSolutions (the company he ultimately sold for $6 million in 1990), his partner, Martin Woodall, told him about an “amazing house” going into foreclosure. It was a home the owner had spent three years building and a “dream home” to the original owner’s wife and whole family, Cuban said. 

But unfortunately, the owner was forced to sell the home when the stock market crashed, and he lost everything. So, Cuban, who’s currently worth about $9 billion, bought the 24,000-square-foot mansion in Dallas sight unseen, calling it his one “why the f–k not purchase.” He still resides there, and Zillow estimates show it’s currently worth $22 million.

“I’d never seen the house. I saw some pictures. I’d never been there. I was like, F–k yeah. I’m a billionaire,” Cuban said. Essentially, the idea is that buying a home at a discount doesn’t inherently change its value. So when Cuban eventually goes to sell the home someday, he’ll make a pretty penny—at least about $10 million based on the current estimated value of the home (although it could be closer to $28 million, according to the Zillow estimate range).

Buying at a steep discount is “the best guaranteed return on investment” you can make, Cuban said, a methodology he uses for most of his purchases. 

“Saving 30% to 50% buying in bulk—replenishable items from toothpaste to soup, or whatever I use a lot of—is the best guaranteed return on investment you can get anywhere,” Cuban said in a 2010 Forbes interview. The mansion was the same principle, just on a much larger scale.

The former Dallas Mavericks owner also used the home purchase example as a cautionary tale about never taking wealth for granted. He also outlined his four-rule framework for becoming a millionaire, which includes mastering a skill, learning to sell, staying curious, and keeping learning—then start a company once you have those foundations.

“You have to know how to sell,” Cuban said. “You don’t want to be in a position where you’re dependent on other people.”

Billionaires approach finances differently

Cuban’s purchase is a window into how the ultra-wealthy think about real estate differently from average Americans, who would likely think it’s insane to purchase a home they’ve never actually seen in person.

Where most buyers shop for a home, Cuban shopped for a better financial position. The mansion is less a lifestyle acquisition (that was just a bonus for him) than an asset with favorable entry terms. Some billionaires, who would presumably be able to purchase a home outright, will also take out mortgages as a more savvy financial decision. It’s because most of the wealth held by ultra-high-net-worth people is tied up in investments, stocks, and bonds, and they don’t keep as much cash on hand.

“Ultra-high net worth individuals think differently about liquidity and leverage,” Miltiadis Kastanis, executive director of sales at Compass, previously told Fortune. “They’d rather keep their money working for them in investments, businesses—or even art—rather than tying it all up in one property.”

For Cuban, the purchase also signals continued confidence in hard assets at a moment when even some of the world’s most sophisticated investors are questioning where to park capital. Real estate offers something that stocks and crypto don’t always promise: a floor built into the purchase price itself.

Still, it’s important for the average American to make financial decisions that work for them, too.

“The takeaway for the average buyer isn’t to mimic [billionaires’] precise approach, but to understand the principle,” Evan Harlow, real estate agent at Maui Elite Property, previously told Fortune. “Sometimes the smartest financial move isn’t paying everything off, but keeping your money flexible and working for you.”