Last November, Andreea Matei made money from her Amazon side hustle for the first time. It was $1.28, and she cheered.
The money hit her bank account after she posted a 75-second video review of an electrolyte powder, as a part of the Amazon Influencer Program — which pays members commissions if someone buys a product after watching one of their posts.
It wasn't much, but considering how easily she earned the cash, Matei knew she was onto something, she says.
Since then, Matei estimates she's posted almost 1,000 reviews, which each take up to 20 minutes to film and edit, she says. They've earned her $21,700 in eight months, an average of $2,700 per month, according to documents reviewed by CNBC Make It.
She spends a maximum of three hours per week filming, recording voiceovers and editing the video reviews from her house in Fort Collins, Colorado, she says.
"Once you create videos, it's totally passive," Matei, 47, adds. "I have not had any time to make videos this week, and the money still keeps coming in."
Matei is something of a side hustle expert. For her full-time job, she runs a media consulting site called Launch Grow Joy, where she teaches clients how to grow their small businesses and side gigs.
Her golden rule, she says: Find an audience, listen to what it wants and deliver.
Her other current side hustles include a podcast, YouTube channel and health content website. Most of them earn money through ads or affiliate marketing links, she says. None have been as lucrative for her as reviewing products on Amazon.
Matei discovered the program while watching a YouTube video called "the world's easiest side hustle." She applied, and because she'd built a substantial social media following — more than 12,000 followers on LaunchGrowJoy's Facebook page — she was accepted.
The daily payouts grew past $1.28 quickly, Matei says: "I made $40 a day, then $50 the next day, then $100. I had to keep going. It was so much fun."
Now, she typically reviews two or three products in the morning, so she can focus on running LaunchGrowJoy.com during the day. She tries to "stockpile" videos, so she can occasionally pause the side hustle while still making money.
At first, she reviewed products she could find around her house, or family members' homes. Now, Amazon sellers also send her free products and pay her to review them on her social media channels, she says.
Matei's success may not be replicable for everyone: You need a "meaningful social media following" on "YouTube, Instagram, TikTok or Facebook" to be accepted, according to the program's site.
The payouts are also highly variable, depending on the latest tweaks to Amazon's algorithms, she says. Amazon didn't immediately respond to CNBC Make It's request for comment.
"Your income definitely changes based on whatever Amazon is testing," says Matei. "I can go from having a $280 day to only making $50 the next because they change the placement of the video."
Matei says the side hustle keeps her from getting burned out at her day job, and the extra cash is obviously nice. Once, she used some of her earnings to buy a $249 treadmill on Amazon — and then reviewed the product, making all of her money back and then some, she notes.
"Amazon is fickle, so I don't want to put all my eggs in one basket," Matei says. "But my goal is to make it a six-figure side hustle on top of my regular business."
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