It’s officially summer, and with the heat comes travel and expenses like concerts, trips to the amusement park and a new wardrobe. To avoid breaking the bank, you may want to consider picking up a summer side hustle to bring in some extra cash.

CNBC Make It has talked to plenty of real people who show you can make more than just a couple extra bucks here and there — their side hustles typically bring in more then $100,000 per year.

“I’ve been doing [my side hustle] for about three and a half years now, and I wouldn’t do anything else,” Sophie Riegel, a part-time online clothing reseller, told Make It. “I love it so much. It makes me so happy.”

Here are four ways you can start earning this summer and maybe even have some fun while you’re at it.

Riegel’s main job includes work as a professional writer, mental health coach and speaker. She told Make It that she spends around 25 hours a week on her side hustle.

Much of Riegel’s success comes down to her research on everything from item value to restocking schedules at local stores.

“Technically, the thrifting takes the most time,” Riegel told CNBC Make It. “But it doesn’t feel like work to me.”

Jim Battan spent $110,000 building a pool at his home in West Linn, Oregon back in 2012. Ten years later, the pool “has paid for itself and more,” Battan told Make it in 2022.

By renting his pool by the hour on an app called Swimply, Battan made $177,000 in less than two years.

Not everything goes swimmingly, Battan warned. He had to learn a lot about pool chemistry and management, and estimated checking the pool’s chemicals 5 to ten times a day. It’s a time-consuming side hustle, he said, but folks can do it if they put in that extra effort.

“I think of my pool as an investment and I take it really seriously,” Battan said. “But there are all kinds of hosts out there that I see posting on the Facebook group that say, ‘Hey, I put a bunch of chlorine in. Is that good enough?’ And I think to myself, ‘That’s just the beginning of it.'”

By day, Kelly Gordon is a superyacht captain. Also, by day, she spends about five hours a week creating social media content, a side hustle she told Make It brings in $10,300 a month.

Gordon stumbled into yachting after attending a wedding reception on a boat in 2007. She told Make It she “didn’t even know port from starboard,” but returned to the yacht the next day and asked the captain everything there was to know about the profession.

Now Gordon shares the ins and outs of yachting with viewers on Instagram. She brought in $124,000 in revenue in 2023 through sponsorships, merchandise sales, ads and affiliate marketing and public speaking engagements.

Even though she’s found success creating content, Gordon isn’t leaving her day job. Her side hustle works because she’s still yachting.

“I’m not done running boats anytime soon,” Gordon said.

He spends eight to 10 hours a week cleaning, managing and booking his cars, in addition to time spent developing relationships with local repair shops. Echeverria told Make It that the success of his side hustle depends on “meeting the right people and building trust with them.”

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