Real estate investing can yield a lot of passive income.

A lot of people want to time the market, but it is time in the market, according to property investor and early retiree Michael Zuber. You will become wealthier the longer you hold an asset. It is amazing what happens to a portfolio after 10 years of ownership.

Insider spoke to people who have used real estate as a tool to build wealth. The following investors have been verified by Insider for their claims about income and property ownership.

Here is how they did it.

At the age of 23, Todd Baldwin invested in his first property. He is on track to hit a net worth of $20 million by the time he is 35.

Todd Baldwin
Seattle-based real estate investor Todd Baldwin.
Courtesy of Todd Baldwin

Todd Baldwin bought his first property at the age of 23. He made it work financially by house hacking, or having rent-paying roommates, which allowed him to live in his own home.

He was able to save more money because he was living for free and collecting rental income. Baldwin had a net worth of $1 million by the time he was 25. At 28, he became a multi-millionaire and decided to double down on real estate.

Real estate is a path to wealth, according to the 29-year-old.

She bought her first home at the age of 22 and now owns five properties in Boston and Augusta, Georgia. She made $43,000 in rental income.

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Boston-based real estate agent and investor Karina Mejia.
Courtesy of Karina Mejia

After graduating, Boston-based real estate investor and realtor Karina Mejia lived at home and worked three jobs to save up for a down payment.

If you have the ability to live with family at the start of your career, it doesn't have to be as big of a sacrifice as it may seem, said Mejia, who financed her first home with an FHA loan and put about $20,000 down. It is a smart financial thing to do for the first year or a few months as you are getting started and paying down your loans.

She has properties in Boston and Augusta, Georgia. She lives for free in one of her properties in Boston.

Michael andOlivia Zuber own over 100 units and earn over $100,000 a month in rental income. They were able to retire comfortably in their 40s because of their real estate portfolio.

A couple wearing sunglasses takes a selfie in front of the Golden Gate Bridge
Michael and Olivia Zuber invest in properties in Fresno, California.
Courtesy of Michael and Olivia Zuber

After losing a lot of money in day-trading, Michael andOlivia Zuber decided to invest in real estate. It started as a way for them to get back on track financially and rebuild their nest egg, but turned into a path to financial freedom.

The Bay Area-based couple saved up enough to purchase their first property, a $107,000 single-family home, by cutting back on things like eating out, entertainment, and vacations in order to save for their first rental property.

They lived on half of their income for many years in order to save and buy more real estate. They were able to quit their 9-to-5 jobs by 2015. Michael left his software job.

Peter Keane-Rivera bought his first property at 25 despite having student debt. He owns nine units between his two properties and earns $102,840 in rental income a year.

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Seattle-based real estate investor Peter Keane-Rivera.
Courtesy of Peter Keane-Rivera

Peter invested in his first property at the age of 25. He came up with the money for the down payment from his early investment in the digital currency.

His mortgage payment and private mortgage insurance cost him $2,000 a month. The house hacked and found two roommates to fill the other rooms. He rents out the other two rooms in his house for $725 and $900 a month. He was paying about half of what he was paying as a renter.

He has nine tenants and owns two properties. He lives for free in one of his homes because of his rental income. He wants to quit his day job in the next two years and focus on real-estate investing.