Four ways to make money through side jobs with an annual income of at least 100,000 yuan.

In recent years, side hustles have become increasingly popular among Americans. Some people are looking to raise money for a house, some for a new car, and others to earn extra income for holidays.

“CNBC Make It” interviewed many individuals who have been successful in the side hustle arena. Their experiences indicate that not only can you make some extra cash through side hustles, but their side gigs often bring in over $100,000 in income annually.

According to a freelance outlook survey released by the freelance platform Upwork in December 2023, 38% of the American workforce (approximately 64 million Americans) engaged in freelance work in 2023, an increase of 4 million professionals from 2022. While some work full-time in freelancing, many others do it part-time as a way to supplement their income.

“I have been doing side hustles for three and a half years, and I wouldn’t do anything else,” part-time online clothing reseller Sophie Riegel told “CNBC Make It.” “I love it. It makes me so happy.”

Here are four methods summarized by “CNBC Make It” that you can start making money this summer.

One might turn “selling unneeded items” into a long-term side hustle. During the Covid-19 pandemic in 2020, Riegel, then a freshman at Duke University, started selling old clothes from her closet online out of boredom, earning $200. After tasting success, she began thrifting at thrift stores and reselling the finds for profit.

In 2023, she made $123,800 reselling clothes on online markets like eBay, Poshmark, and Mercari.

Riegel’s main occupations include professional writing, mental health coaching, and speaking engagements. She told Make It that she spends about 25 hours per week on her side hustles.

In 2012, Jim Battan spent $110,000 to build a swimming pool at his home in West Linn, Oregon. Battan told Make it in 2022 that ten years later, he not only recovered the cost of the pool but also made a profit.

By renting out his pool by the hour through an app called Swimply, Battan made $177,000 in less than two years. However, he cautioned that not everything went smoothly. He had to learn a lot about pool chemistry and management, estimating checking the pool chemicals 5 to 10 times a day. He said it was a time-consuming side hustle, but with extra effort, it could be done.

Kelly Gordon is a super yacht captain. She told “CNBC Make It” that showcasing her work-life through content creation brings in $10,300 in income monthly.

Gordon stumbled into the yacht industry by chance after attending a wedding on a yacht in 2007. She admitted that at the time she “didn’t even know the difference between port and starboard,” but the next day back on the yacht, she learned all she could about the profession from the captain.

Now, Gordon shares her yacht experiences with fans on Instagram. In 2023, she made $124,000 through sponsorships, merchandise sales, advertising, affiliate marketing, and public speaking engagements.

Despite her success in content creation, Gordon hasn’t given up her daytime job. The reason her side hustle works is that she continues to work on yachts.

With an increase in summer travel, people across the United States often opt for rental cars. Andrei Echeverria’s side hustle offers an alternative to traditional car rental services. By renting out his six cars through an app called Turo, he can make up to $14,000 per month, according to financial documents reviewed by “CNBC Make It” in 2023.

Living near Boston Logan International Airport gives Echeverria an advantage in finding rental clients compared to other Turo users. Allowing him to set prices, Echeverria can offer more attractive rates than rental companies.

He spends 8 to 10 hours per week on cleaning, maintenance, and car scheduling, in addition to building relationships with local repair shops. Echeverria told “CNBC Make It” that the success of his side hustle depends on “meeting the right people and building trust with them.”

According to Riegel, the most important quality one must possess to succeed in this side hustle is consistency and perseverance.