The idea of financial independence can mean different things to different people, but one common way to define it is having enough money that you no longer need to rely on a job, a paycheck or someone else to sustain your lifestyle.

While the path toward financial independence can feel daunting, there has been one tried and true method of success: live below your means and invest what you save.

That's exactly what Shu Matsuo Post did to achieve the freedom he has today. Over the course of about seven years, the 38-year-old consistently poured over 50% of his and his wife's dual income into real estate investing.

Now, Matsuo Post owns a $2 million real estate portfolio consisting of six rental properties located in the U.S. and three in Japan, according to documents seen by CNBC Make It.

"I'm very fortunate to be able to say this, but I don't have to work for money," Matsuo Post told CNBC Make It. "I enjoy earning money, but I can focus on what I want to do... it's completely the other way around."

Today, Matsuo Post lives in Japan with his wife and two kids. Besides managing his investments, he also creates online educational content about real estate investing and runs his own consulting business Post FI, which helps foreigners purchase property in Japan.

Beginning of real estate investing journey

Matsuo Post's journey toward financial independence was not straightforward. Pivoting his career multiple times, he worked in industries like journalism, retail and technology before entering real estate.

Born and raised in Japan, he moved to the U.S. at 15-years-old and ended up staying for about eight years to study and begin his career. Following his stint in the U.S., Matsuo Post also worked in Hong Kong for several years before settling down back in Japan with his wife, Christina, seven years ago.

After getting married in 2017, Matsuo Post and his wife decided to combine their finances. When they began investing, they focused primarily on index funds and ETFs, but ultimately decided that they wanted to be more active with their investments instead of waiting around for stock market returns.

"We found real estate and kept talking about it, and then we decided that we can live off of one income," Matsuo Post said. They chose to live off of Christina's income from teaching and saved all of Shu's salary for their first property.

"For us, we were super fortunate to be able to do that having relatively high paying jobs at the time and we just saved quite a bit," said Matsuo Post. The couple ended up saving over $250,000 before investing in their first property, he said.

In 2018, Matsuo Post and his wife purchased their first property — a duplex in Minnesota — for a total of $216,500, according to documents seen by CNBC Make It. Just one year later, he purchased three more rental properties across Minnesota and New York.

Leaving the corporate world

In September 2022, Matsuo Post was laid off after his company shut down the business division that he worked in. But after evaluating his finances, he realized that it was no longer necessary to find another office job.

"So after I was let go from the startup, I had a choice to go back to the corporate world or to start something [of my own]," said Matsuo Post. Ultimately, he decided that he wanted to spend more time with family, so he chose to leave the corporate world for good.

Shortly after being laid off, Matsuo Post started his YouTube channel, which has garnered over 100,000 subscribers, and in 2023, he started his real estate consulting business Post FI, or Post "Financial Independence."

"I'm never going back," Matsuo Post said. "Achieving that financial independence is absolutely important, but retirement and not having to work ever — I realized, it's not something that I wanted. I wanted engaged work that I didn't need to retire from."

"If that generates money, that's great, and if it doesn't, that's okay too, because you have other forms of income coming in to support your lifestyle," he said.

3 tips on achieving financial independence

When asked about the guiding principles he used to achieve financial independence, Post said:

1. Invest in yourself first. Read books, attend seminars and learn from others who have already achieved goals similar to your own.
2. Increase your earning potential. Saving won't make you rich but it allows you to have money, which helps you to take bigger risks with higher potential payouts.
3. Stay frugal. Save more than 50% of your income. 

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