In 2016, Nicole Tocci carefully removed the buttons off her vintage Chanel clothing, spent about three hours polishing them, added a hook and attached them to thin silver and gold chains.

She started selling the pendant necklaces in her Berkeley Heights, New Jersey-based tanning salon, Nikki Tans and at pop-up events. Their popularity eventually convinced her to build a standalone website for her side hustle, called One Vintage Button, at the end of 2020. In the first full year of business, the side hustle brought in $90,000, according to documents reviewed by CNBC Make It.

This year, Tocci has already made $351,900 selling repurposed button necklaces, primarily sourcing her vintage finds from Chanel clothing. That's just over $39,000 per month, on average — and she only spends 20 hours per week on the side hustle, she says.

"Sometimes, your intuition is dead-on right," Tocci, 45, tells CNBC Make It. "I started testing the necklaces at my boutique and gathering feedback from high-end clientele. I knew immediately that they were a winner."

Here's how Tocci combines her business knowledge, fashion background and customer service expertise to run a successful six-figure side hustle:

From swimsuits to spray tans

Growing up, Tocci was her friends' styling confidante. In college, while studying fashion at Montclair State University, she worked in Nordstrom's swimsuit department.

"Even though it was a part-time job, I think the foundation of what Nordstrom's believed in was so helpful for me in fashion and owning my business," Tocci says. "They teach you how to treat and follow up with customers and why they run their sales quarterly. I used a lot of what I learned in my businesses today."

After graduating, Tocci worked a couple of sales jobs and ran a closet-organizing business for almost four years. But Tocci lost clients during the Great Recession in 2008, so she decided to pivot. It was a long process, but two years later, she finally used $30,000 from her savings to open Nikki Tans, a storefront for spray tans, styling and beachwear.

Nikki Tans brings in up to $350,000 in revenue annually, Tocci says. "We're in an affluent area, so my clients tend to be fashionable, well-educated," she adds. "I think most of my clients look to me for fashion advice and feel that I'm a trendsetter."

How to build a button business

Tocci leveraged that trust to start One Vintage Button. Launching the side hustle cost roughly $40,000, she says, with the majority going toward sourcing Chanel clothing with unique buttons over the course of a year.

That remains the most difficult part of the job, she says: Tocci spends up to six hours per month searching consignment stores for pieces of vintage clothing with buttons that meet her qualifications for color, size, condition and year of manufacturing. Each piece of clothing she buys can cost anywhere from $400 to $1,500, and she needs approximately 40 to 50 buttons for each quarterly drop.

Depending on the season, Tocci also spends up to $1,100 on social media marketing — mainly on Instagram — to grow her customer base. In February, One Vintage Button had its highest-earning month a couple of weeks after an Instagram micro-influencer named Cassidy Michelle posted about one of Tocci's necklaces.

One Vintage Button is a one-woman operation, and Tocci says she aims to keep it that way. Still, she says she wants to scale up by negotiating with local consignment shops get her necklaces into wholesale markets, and expanding her side hustle's styles and designers.

Ideally, One Vintage Button can be a financially sustainable side hustle alongside Nikki Tans for years to come, Tocci adds.

"Sometimes you just have that physical vision of what your business is going to be," she says. "I'm sure most entrepreneurs would agree: That moment where you can visualize the product — what it looks like, who's buying it — you know you have something special."

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