Sarah and Jamie McCauley are landlords, YouTubers, Walmart pallet flippers, eBay resellers and Amazon product reviewers — and those are just their active streams of income.

The McCauleys make their money by researching what makes side hustles profitable, testing them and teaching others how to do the same on YouTube. The Grand Rapids, Michigan-based couple earned nearly $140,000 from eight streams of income last year, according to documents reviewed by CNBC Make It.

They’re particularly good at two types of gigs, they say: anything involving real estate and their YouTube channel itself, where they share their side hustle exploits with at least 146,000 subscribers.

“If you’re looking to just make some extra money on the side, maybe pay off a credit card debt or pay for a vacation, I think that is doable for nearly everybody,” says Jamie.

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The McCauleys are part of a side hustle revolution, a growing number of Americans who supplement income with multiple jobs. More U.S adults — about 39%, according to Bankrate — have side hustles today than ever before, whether out of necessity, precaution or a desire to increase their earning power.

Ease of starting is at an all-time high: Platforms like Amazon, Airbnb and Fiverr offer instant access to paying customers. But with competition also rising, it’s hard to build a side hustle that regularly brings in revenue.

Make It spoke with a selection of Americans with successful side hustles to learn how they built their businesses, and used them to fund a wide variety of financial goals. Every respondent highlighted four common traits that helped drive their success:

No matter what you sell, you need people willing to buy it. Jenny Woo says her side hustle is successful for a simple reason: She researches her audiences intensely, and tailors her products specifically to them.

Woo is an adjunct lecturer at the University of California, Irvine, a freelance business consultant and the teacher of an online course about emotional intelligence. Her one-woman side hustle, called Mind Brain Emotion, sells 12 different emotional intelligence-themed card games.

It brought in $1.71 million on Amazon last year, according to documents reviewed by Make It.

Woo’s first deck of cards, “52 Essential Conversations,” was tailored toward parents who — like her — wanted to connect with their kids and build their emotional intelligence skills. She joined parenting Facebook groups and observed users’ posting, commenting and liking habits, she says.

After selling $10,000 worth of the game in a 2018 Kickstarter campaign, Woo kept researching. She conducted a survey of her consumers, and learned that “overwhelmed” teachers looking to support children’s social and emotional development made up a significant portion of her audience, she says.

Her second deck, “52 Essential Relationship Skills,” was built for those teachers. It didn’t sell as well as her first deck, but it taught Woo that she could broaden, and combine, her audiences.

Woo applied that lesson to her third game, “52 Coping Skills.” She started with her own experiences working with college students during the Covid-19 pandemic and combined it with her continued research on teachers and parents, she says.

It’s now Mind Brain Emotion’s top-selling game, says Woo.

Woo sells on Amazon, which has a broad reach, to collectively rope in Mind Brain Emotion’s hyper-specific audiences. Tim Riegel’s products have a more singular customer base, so he sells on Etsy, a marketplace known largely for homemade and handmade goods.

Riegel, a full-time general manager at a sheltered workshop, makes firepits from recycled tank ends in Lamar, Missouri, and sells them under the name Mozark Fire Pits. His average product weighs 225 pounds, and sells for $950.

Mozark Fire Pits brought in approximately $202,000 on Etsy last year, according to documents reviewed by Make It. Riegel maintains a 40% profit margin, he says.

Riegel chose Etsy over platforms like Amazon, Wayfair and Overstock because it felt more user-friendly, and a better fit for his personalized products, he says. He also sells on Facebook Marketplace, which costs him more in advertising — but less in shipping costs for customers within a 200-mile radius, he adds.

That kind of platform analysis is valuable, no matter what kind of side hustle you run.

If you sell a service, instead of a good, you might consider platforms like Fiverr and Upwork — popular among photo editors, marketing writers and voiceover artists — or Taskrabbit, known for labor-intensive side hustles like cleaning or repair work.

Or, opt out of those platforms entirely. If your gig is something that many other people also do, try finding marketplaces with more narrow niches like Contently, Skyword or ServiceScape, recommends side hustle expert Kathy Kristof.

“One of the problems I see with a lot of freelancers is that they go to the best-known online platforms … and those platforms are so saturated with people who have been there for, often, decades,” says Kristof, whose blog SideHusl has reviewed more than 500 different side gigs.

No matter your platform, you’ll need to stand out. A good listing can help: clear and concise, written for your intended audience, free of typos, with high-quality graphics and some search engine optimization (SEO).

Becky Powell, a kindergarten teacher based in Beaverton, Oregon, has a side hustle selling worksheets for other educators on an online platform called Teachers Pay Teachers. Many of her worksheets focus on her personal specialty, teaching children sight-reading skills.

Her side hustle didn’t take off until she embraced SEO. When she uploaded her first worksheets, she titled them, “Creating sight words with pattern blocks.” Sales slowly trickled in.

Her husband Jerome, who has a business background, suggested a simpler title, like “Hands-on sight words.” The sight-reading worksheets quickly became her bestselling products, Powell says.

Powell’s store brought in $125,500 in 2022 revenue, according to documents reviewed by Make It. Her husband also sells worksheets on the platform, and they’ve used their combined earnings to fund vacations and pay down their mortgage and student loans, Powell says.

“You have to have passion and knowledge,” she says. “You also have to have a business sense [and understand] SEO.”

Once you gain enough customers, work to turn your sales into positive reviews, so you appear higher in platforms’ search results, Kristof advises. Customer service, prompt shipping and quality control can usually earn you a good online reputation.

The McCauleys have a rule for their ever-changing collection of side hustles: “You either have to be one of the first to get there, or your approach has to be very unique and different to be successful,” Sarah says.

But being first or unique doesn’t guarantee long-term success. In 2020, the couple was early to a side hustle trend: pallet flipping. At local warehouses, they’d buy pallets of returned goods from Amazon, Walmart or Target. They’d unbox the pallets, discover their contents and resell the items for a hopeful profit.

From December 2020 to December 2022, the McCauleys made about $19,500 in pallet-flipping profits, they estimate. Their most popular unboxing YouTube video got 5.4 million viewers, translating to an additional $30,000 in advertising revenue, says Jamie.

Last year, more Americans hopped on the pallet-flipping trend. Pallet prices rose, resale values dropped and a slew of unboxing videos diluted the McCauleys’ viewership. “The pallets became not really worth our time … from the standpoint of time over money,” says Sarah.

Four years ago, the McCauleys would’ve simply moved onto their next side hustle. Now, they’re feeling the strain of constantly building new gigs from scratch, and starting to reorganize their income streams into a smaller number of longer-term projects.

Instead of flipping their current home renovation project in Northern Michigan for a profit, for example — something they’ve done multiple times — they’ll keep it as their own vacation house and part-time Airbnb rental, they say.

“We always knew [side hustling] was going to have an expiration date,” says Jamie. “It’s a young person’s game, to always be looking for what’s next.”

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Supplements, superfoods, and health hacks are advertised constantly to those looking to live a long, healthy life, but focusing on just those quick solutions is not very effective, according to leading longevity researcher Dan Buettner.

On a recent episode of “Ten Percent Happier with Dan Harris,” Buettner, who popularized the world’s Blue Zones, spoke about how attempting to achieve good health through extreme measures can be counterproductive.

In “five corners of the world,” blue zones are living on average eight years longer than Americans, Buettner said. Yet, “none of them are tracking their steps, or taking superfoods, or running down to Costa Rica for stem cells.”

There’s something that people in Blue Zones do that most Americans don’t, and probably should, he noted.

“They don’t try to live longer. They don’t proactively pursue health or longevity, which I think is the most important insight that is so under-acknowledged,” Buettner said during the podcast episode.

“Trying to pursue health, whether it’s through diets or exercise programs,” Buettner said, “they’re great business models but they’re horrible at delivering any meaningful outcomes.”

Instead, residents of blue zones prioritize improving their personal relationships and developing a sense of community, he said.

“In blue zones, people live a long time not because they pursue health. It’s because it ensues,” Buettner said. “They live in an environment wherein their micro unconscious decisions are slightly better all day long, as a result of their surroundings.” And this includes who they surround themselves with.

Maintaining positive connections with people who engage in healthy activities like walking daily or having plant-based meals with loved ones is something Buettner highly recommends for longevity.

“If they want to live longer, lose weight, get more exercise, eat better,” Buettner said, “they’ll get a far better return on their effort, time and money by shaping their environment than they ever will by buying a gadget or thinking they’re going to change their behavior for long enough to make any difference.”

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When Mark Cuban sells a business, he always sets aside some of the proceeds for one specific purpose: divvying it up among the company’s employees.

“In every business I’ve sold I’ve paid out bonuses to every employee that was there more than a year,” Cuban posted Tuesday on social media platform X. The bigger the acquisition, the larger the payout: 300 of Broadcast.com’s 330 employees became millionaires when the audio streaming service sold to Yahoo for $5.7 billion in stock in 1999, Cuban wrote.

Cuban started the practice after selling his first company, a software firm called MicroSolutions, for $6 million to CompuServe in 1990. He took 20% of the total sale price, he tells CNBC Make It, and paid it out to 80 employees — which would equate to $15,000 per staffer, if distributed equally.

Cuban did something similar upon selling his majority stakes in HDNet, now known as AXS TV, in 2019 and the NBA’s Dallas Mavericks last year, he wrote in his post. “And only HDNet had any layoffs right after the sale,” he added.

Cuban’s co-founding and sale of MicroSolutions marked his first big entrepreneurial success and a triumph over setback: He nearly went broke after his secretary stole roughly $82,000 from the company.

“It was f—ed up,” Cuban told Barstool Sports’ “Pardon My Take” podcast in 2020. It also presented a silver lining, he added: “It made us get our s— together.”

The business bounced back, and Cuban sold MicroSolutions five years later, making him a millionaire. “You have to hustle the most when you think it’s the darkest,” he said.

In 1995, Cuban invested in and took operational control of AudioNet, the streaming platform that eventually became Broadcast.com. The business idea was met with skepticism at a time when the internet was still fledgling, he told CBS’s “Sunday Morning” last year.

“There was nobody doing it. Nobody,” Cuban said. “People thought I was an idiot.”

Upon selling Broadcast.com, Cuban received a large portion of Yahoo stock, which was considered highly valuable at the time. But instead of holding onto it, he quickly cashed out. He was happy with the money he’d earned and suspected the stock market was overpriced, he told GQ in 2022.

Months later, the dot-com bubble burst and Yahoo’s share price sank. “It taught me a hell of a lesson: When you just chase dollars, it never works out well,” Cuban said.

Last year, Cuban sold a majority stake in the Mavericks to the Adelson and Dumont families, who run Las Vegas Sands Corporation, in a deal reportedly valuing the franchise at roughly $3.5 billion. He retained a 27% ownership stake and control of basketball operations, the Associated Press reported at the time.

The deal ended Cuban’s longtime status as an NBA majority owner. In 2000, the newly minted billionaire purchased his initial stake in the team for $285 million — without negotiating or trying to push the price down by even a penny.

“It was all about fun,” Cuban told “The Draymond Green Show” podcast, in an April episode. “That was like a dream … I didn’t even negotiate, I was just like, ‘Yes, whatever.’”

Cuban’s current net worth is $5.4 billion, according to Forbes.

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Prices for everyday items continue to rise across the country, but in some places it’s worse than in others — especially for residents in the Dallas-Fort Worth area.

Although the national year-over-year inflation rate has dropped to 3%, it has hovered around 5% in Dallas-Fort Worth in 2024, according to a new WalletHub report.

That’s second only to Honolulu among a selection of 23 major U.S. metro areas, and higher than other cities known for a relatively high cost of living, including New York City and Los Angeles. Inflation in Dallas-Fort Worth has also risen steadily by 1% over the past two months — making it the nation’s worst city for inflation, according to the study.

The relatively high inflation rate can be attributed to a “significant housing shortage, along with restrictive government policies that limit new construction,” which has caused housing prices in Dallas-Fort Worth to soar, says WalletHub analyst Cassandra Happe.

Other factors include “substantial increases in energy prices″ including electric bills and persistent inflation in key areas like medical care and transportation services. Rising medical care costs have been linked to hospital consolidation in recent years, while transportation costs are largely related to the effects of urban sprawl, according to the Dallas Morning News.

Aside from Dallas-Fort Worth, Honolulu is the only other city in the study with year-over-year inflation that’s 5% or higher.

Below are WalletHub’s rankings of metro areas with the worst inflation, from worst to best. The rankings are based on an index that’s weighted equally between year-over-year inflation and inflation over the past two months as of June 2024. 

• Two-month change: 1.00%
• One-year change: 5.00%

• Two-month change: 0.70%
• One-year change: 5.20%

• Two-month change: 1.10%
• One-year change: 4.20%

• Two-month change: 1.00%
• One-year change: 3.40%

• Two-month change: 0.60%
• One-year change: 4.00%

• Two-month change: 0.60%
• One-year change: 4.00%

• Two-month change: 0.80%
• One-year change: 3.40%

• Two-month change: 0.80%
• One-year change: 3.30%

• Two-month change: 0.40%
• One-year change: 3.80%

• Two-month change: 0.50%
• One-year change: 3.20%

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Almost 60% of the caloric intake of the average American diet is coming from ultra-processed foods, according to a 2017 paper published in the journal Population Health Metrics — and that’s concerning to health experts.

“Ultra-processed foods contain ingredients that we generally wouldn’t find in our kitchen, and they often contain high amounts of sugar and salt,” says Jinan Banna, registered dietitian and professor of nutrition at the University of Hawaii.

“They may also contain additives, and they often are stripped of their nutritional values. So they may have very little vitamins and minerals [and] fiber.”

Eating ultra-processed foods often can lead to a higher risk of developing health conditions like dementia, type 2 diabetes and heart disease, according to doctors in the American Medical Association.

That’s why Banna limits her consumption of ultra-processed foods and encourages you to do the same. Here’s the highly processed food that she never consumes.

“Some [ultra-processed foods] I would never consume, such as soda,” Banna tells CNBC Make It.

“Soda doesn’t have any nutritional value other than just calories in the form of sugar. So they’re empty calories, which don’t give us any of the nutrients that we need.”

When you drink soda, it is digested very quickly and can cause you to feel hungry, she adds, which can lead you to eat more food than you planned to.

Instead of soda, Banna opts for different types of tea and water, still or sparkling.

“Sometimes I drink a cold hibiscus tea. Plain water, of course, is a great alternative,” she says. “Even coffee can be an option, of course, consumed in moderation.”

A recent preliminary study that was presented last week at a meeting held annually for the American Society for Nutrition took a close look at dietary data collected in 1995 from more than 500,000 Americans between the ages of 50 and 71. The data was used to determine if there were connections between dietary choices and mortality rates over the span of almost 30 years.

Out of 124 foods, ultra-processed drinks was the No. 1 food that people who had the highest intake of ultra-processed foods consumed.

“Diet soft drinks were the key contributor to ultra-processed food consumption. The second one was sugary soft drinks,” the study’s lead author Erikka Loftfield told CNN.

Beverages make up a significant portion of dietary intake. So, these types of drinks — like diet sodas and energy drinks — are the processed food that people seem to consume more than others, Loftfield said.

The study also found that the lifespans of those who eat a diet high in ultra-processed foods may be shortened by over 10%, according to CNN.

As a rule of thumb, Banna recommends using the 5/20 method when checking the nutrition labels on the foods you eat.

“You can use the daily value,” she says. “That’s an easy way to know whether the food is generally high or low in a particular nutrient.”

Check the daily value percentages of specific nutrients like sodium, sugars or saturated fat, Banna suggests.

“The idea is, if [it’s] 5% or less, then the food is generally low in that particular nutrient. If 20% or more, you can consider the food high [in the nutrient],” she says.

“So that’s just a quick way to glance at the label and know if a food contains a little bit or a lot.”

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