5 successful celebrity side gigs you didn't know about

Jay Leno and President of NYSE Group at Intercontinental Exchange, Inc.
Mireya Acierto | Getty Images
Jay Leno and President of NYSE Group at Intercontinental Exchange, Inc.

The lifestyles of the rich and famous can be pretty amazing. From luxurious European vacations to expensive purchases, celebrities can afford to spend hundreds of thousands without even thinking about it.

However, not every celebrity is comfortable spending all that money. In fact, several have side gigs to establish another income stream to diversify their finances; it's a big part of their money-making philosophies.

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Here are five celebrities with some serious side hustles.

1. Erykah Badu

Grammy-winning singer and songwriter Erykah Badu has a lucrative career producing and recording albums. She's also an actress who has starred in acclaimed films like "The Cider House Rules."

Despite her success in the music and entertainment industries, Badu has another calling: delivering babies as a certified doula.

Erykah Badu performs onstage during the FYF Fest
Rich Fury | Getty Images
Erykah Badu performs onstage during the FYF Fest

A doula provides mental and physical help to an expectant mother before, during, and after labor. Since she started her side career as a doula, she has helped bring 40 babies into the world, reported online health resource BlackDoctor.

Badu discovered her passion after helping a friend through labor.

"I've always had a mothering nature," she said in an interview with People. "But I didn't plan on becoming a doula. I just wanted to care for my family and friends. When I saw the baby, I cried. I knew what I was supposed to do with my life."

According to Parents.com, Badu is also working toward earning a midwifery certification. Once she has achieved that goal, she plans to open birth centers in inner-city neighborhoods.

Badu does not list her rates for her services publically. However, the typical doula charges between $500 and $3,500, depending on where they live.

2. Scarlett Johansson 

As a talented actress, it would seem like Scarlett Johansson has had a privileged life. But that wasn't always the case. Earlier this year, she appeared on "Inside the Actors Studio" and revealed that she struggled with poverty as a child.

Scarlett Johansson appears on Inside the Actors Studio
Bravo | Getty Images
Scarlett Johansson appears on Inside the Actors Studio

"By the time my twin brother and I came around, I think my parents' marriage … had a lot of strain," she said on the Bravo TV show. "We were living on welfare; we were on food stamps. My parents were raising four kids in a low-income household in Manhattan."

That's why it was such a big deal for her when she opened a gourmet popcorn shop last year. She's now balancing her store with her huge movie career.

"It has been a dream of mine and my family for several years to bring our favorite American snack to our favorite European City," she said in a statement. "My hope is for Yummy Pop to become a Parisian snacking staple and a symbol of friendship between my two most beloved cities, Paris and New York."

3. Dwayne 'The Rock' Johnson

Dwayne "The Rock" Johnson might be the ultimate side hustler, with several different jobs to bring in more money.

Behind his drive is a tough upbringing. His parents struggled to afford the basics, and they faced eviction and vehicle repossession.

"We were living in an efficiency that cost $120 a week," he told the Hollywood Reporter. "We come home, and there's a padlock on the door and an eviction notice. My mom starts bawling. She just started crying and breaking down. 'Where are we going to live? What are we going to do?'"

His mother tried to do her best for her son, but they moved 13 times during his childhood.

"That was the tipping point," he told the Hollywood Reporter. "It was about, 'What can I control with these two hands?'"

Dwayne Johnson speaks at Paramount Pictures' presentation during CinemaCon
Gabe Ginsberg | Getty Images
Dwayne Johnson speaks at Paramount Pictures' presentation during CinemaCon

He became a top professional wrestler and later, an actor. But along the way, he's kept multiple income streams coming in. He now runs a small production company, appears on television shows as well as movies, and is writing his second memoir.

With many different sources of income, Johnson ensures he'll always have money coming in — and will never have to worry about eviction notices again.

4. Jay Leno

Jay Leno is well-known for his career as the long-time host of "The Tonight Show" and his multimillion-dollar car collection.

However, Leno isn't the type to spend every penny. Ever since he started working, he made sure to diversify his income streams to bring in extra money.

"I always had two incomes," he told CNBC. "I'd bank one, and I'd spend one."

When he was just starting out, he lived off his earnings as a comedian and saved the money he made working at a car dealership. Later, even with huge contracts and television deals, he still worked multiple jobs. He says that policy gives him peace of mind.

Former Tonight Show host Jay Leno
NBC | Getty Images
Former Tonight Show host Jay Leno

"So many people get to be the age I'm at now, and they've got nothing because they just blew it all," he continued. "I put my money in a hammock and say, 'You relax. I'm going to go work.' And when I come back, I put some more money in the pile.

"It sounds ridiculous, but if everything ends tomorrow, I know I'll be fine."

5. Jeremy Renner

Jeremy Renner is a well-known actor recognized for his roles in movies like "The Hurt Locker" and "The Avengers." But despite his acting career, Renner has another side hustle: flipping houses.

He got started when he was trying to launch his acting career. Like many new actors, Renner was broke. According to Business Insider, he and his friend pooled what money they did have and bought an older home together.

Jeremy Renner attends the premiere of Wind River
Jason LaVeris | Getty Images
Jeremy Renner attends the premiere of Wind River

Originally, they didn't intend to sell it. They just did small renovations to make it more livable, like adding a second bathroom — but then someone offered them double what they paid for the home. That experience helped them get interested in flipping homes, and the pair has sold more than 20 properties since they got started, reported Realtor.com.

Renner credits his side gig with keeping him grounded.

"You run into the Beverly Hilton to do 'Extra,' and then you have a meeting here, and then you go to a red carpet," he said in an interview with The Wrap. "And between all these things, I'm going to pick out tile. I go back to this dirty job site in a suit so that I can tell the electrician where to put light switches. It's just a little moment of reality."

Everyone needs multiple income streams

Although you might not have the same earning potential as Scarlett Johansson or Dwayne Johnson, having multiple income streams is important for your financial security. Having other sources of money can help protect you in the case of an emergency, such as losing your job.

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This article originally appeared on Student Loan Hero.