A former gym teacher who built a hotel empire just became North Dakota’s first billionaire, and his take on money lines up with what many of the world’s richest self-made people say

• Gary Tharaldson is North Dakota’s first billionaire, Forbes reported.
• After selling his hotel empire to Goldman Sachs in 2006, Tharaldson started another one, according to Forbes.
• Tharaldson, like other many other billionaires, said he doesn’t work for money, but because he loves his job.
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North Dakota just got its first billionaire.

Hotel investor Gary Tharaldson may be the richest person in North Dakota, but the newly minted billionaire still thinks estimates of his net worth are a little low, according to Forbes.

“Obviously we wouldn’t sell for that,” Tharaldson told Forbes, “I would say it’s very conservative.”

A 73-year-old former gym teacher, Tharaldson built his fortune by purchasing and operating budget hotels. He bought his first, a Super 8 motel in North Dakota, in 1982, according to Forbes.

After selling 130 hotels to Goldman Sachs for $1.2 billion in 2006, Tharaldson invested in an ethanol plant, an aquifer in Arizona, and property in Nevada, Colorado, and Texas before returning to the hotel business, according to Forbes. He now owns 49 hotels across the country.

Forbes pegs his net worth at $1 billion. But, like many other self-made billionaires, it's not the money that comes first for Tharaldson - it's the work itself.

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"The money is not the factor," Tharaldson told Forbes. "I work because I love what I do."

Business Insider's Hillary Hoffower previously reported that many billionaires enjoy making money more than they enjoy spending it. And a study of the habits of 21 self-made billionaires by Rafael Badziag revealed that billionaires tend to live frugally. Warren Buffett, for example, lives in a home worth less than $300,000, despite his fortune. Similarly, Tharaldson told Forbes that he also lives modestly, with the exception of his 45th-floor condo in the Waldorf Astoria on the Las Vegas Strip.

"I will never quit working," Tharaldson told Forbes. "I've got half-a-billion dollars' worth of projects that are under construction right now, and another almost $900 million that are in the pipeline, so I have a little ways to go before I even think about retiring."