Mark Cuban says this book helped him earn his first $1 million

These Mark Cuban quotes reveal his exceptional work ethic

Billionaire Mark Cuban recently got a little richer: The owner of the Dallas Mavericks and judge on ABC's "Shark Tank" sold his stake in the Boston-based obstacle course company Rugged Maniac, and he about doubled his original $1.75 million investment, according to the Boston Globe.

These days, Cuban can make accumulating wealth look easy. But making his first million required sacrifice. To do what was necessary to get ahead, he says, he was inspired by a book about cutting back: "Cashing in on the American Dream: How to Retire at 35" by Paul Terhorst, he told Money in a 2017 interview.

Terhorst urges readers to focus on your priorities and live well below your means. Downsize houses, cars and other expenses, he suggests, and spend time developing their passions and finding meaning in your lives beyond work.

"I did things like having five roommates and living off of macaroni and cheese, and I was very, very frugal," Cuban told Money.

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Even as the entrepreneur's career began to take off, the lessons he learned in "How to Retire by 35" inspired him to stick to his austere habits. "I didn't have a car that cost more than $200 until I was 25, I think," he says. "It was crazy."

Cuban doesn't regret his beat-up rides and pasta dinners. At the time, his only focus was on preparing for the future and saving up enough so that he could retire comfortably.

"It wasn't like I thought, 'Okay, I'm going to be super rich,'" he says. "I valued time more than anything. I wanted enough money to be able to travel, have fun and party like a rock star, but still live like a student. That was my motivation."

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That's not to say Cuban is unwilling to splurge: If something saves him time, he believes it's worth the cost. In the late '90s, he bought his first private jet, which he still thinks is the smartest thing he ever spent money on. "It is obviously brutally expensive, but time is the one asset we simply don't own. It saves me hours and hours," he wrote in a column for Men's Fitness.

Cuban's not the only billionaire willing to pay for the convenience of time. John Paul DeJoria, co-founder of Paul Mitchell hair products and Patron Tequila, owns three private jets.

"For him, time is a precious commodity and he'll do what he must to preserve it, even if it means spending millions of dollars on his own airplanes," writes Farnoosh Torabi, who shadowed DeJoria on the CNBC show "Follow the Leader." "His jets allow him to conduct meetings on the go and around the country without wasting hours at the airport."

This is an updated version of a previously published article.

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