A full-time government employee with multiple side hustles shares his top passive income hits and flops
From Invention Journals to ATM Empires: How One Engineer Built a Portfolio of Side Hustles
William Butterton has always been a tinkerer.
"I had invention journals when I was a little kid," he told Business Insider. "I always wanted to be an inventor."
For years, those ideas remained sketches on paper. Comfortable in his day job as an electrical engineer at the Naval Undersea Warfare Center in Keyport, Washington, Butterton felt little urgency to build something on the side—until he became a father.
"That's when I started really thinking about how I could bring some extra money in, but without sacrificing that safety net that I had built at my job," he said. "As your family grows, the benefits and incentives that you have at a full-time job, especially a government one, become really important."
His federal position offers a unique advantage: an alternating schedule of 36-hour and 44-hour weeks, giving him predictable windows to experiment with entrepreneurial ventures. What followed was a journey of trial, error, and strategic pivots across three distinct side hustles.
The Most Passive Play: ATM Placement
Butterton first discovered ATM placement through Instagram and TikTok. Intrigued by the low barrier to entry, he did his research.
"The more I looked into it, the more I was like, 'OK, there's really no risk in trying this, outside that original financial obligation of $2,500 to buy the ATM.'"
While he's cautious about the overused term "passive income," Butterton says ATMs come closest to the ideal. "You're only there for 10 minutes to load it up, and then you're on your way."
In 2022, he and a business partner launched Viking Vendors. As of March 2026, they operate five ATMs and three vending machines, splitting roughly $1,500 in monthly profit based on terminal activity summaries reviewed by Business Insider.
For beginners, Butterton recommends starting with ATMs over vending machines, which demand more physical labor and maintenance. Currently, he and his partner spend about an hour per week servicing their eight machines—but scale changes the equation. He knows an operator with over 100 ATMs who spends his days loading machines and struggles to take time off.
Butterton estimates he could double his current fleet while keeping the business relatively hands-off. Still, he's clear about his priorities: "I love owning a business, but I'm not passionate about ATMs." For him, the venture is less about the machines themselves and more about learning the fundamentals of entrepreneurship with minimal risk.
The High-Effort, High-Reward Hustle: Sports Cards
After the birth of his second daughter, Butterton launched a second side hustle—this one born from personal passion. He and a longtime friend had been spending money opening sports cards and wondered if they could monetize the hobby.
They noticed a shift in the market: traditional local card shops were struggling, while online sellers leveraging live-streaming platforms were thriving. In 2024, they hosted their first auction stream on Whatnot, a platform for live video sales. Setup was simple—Butterton mounted a camera in his garage—but profitability required patience and iteration.
Early results were discouraging. "That first stream, we got burned. You're just trying to figure out how to even use the website, and you end up losing money."
They persisted, streaming weekly on weekend nights under the name The Pack Daddies. "For a couple of months there, we were sitting up there for about $5 an hour," he said. "We'd always joke that there's not a job in America that pays worse than this."
Consistency eventually paid dividends. From July through December 2024, they sold approximately $20,000 in inventory. Over the next 10 months, they expanded into Magic: The Gathering and Pokémon cards, pushing sales past $100,000 and growing their Whatnot following to roughly 7,500.
Unlike ATMs, the card business demands significant time: multi-hour live streams, in-person appearances at trade shows, and inventory management involving tens of thousands of dollars in product each month.
"If you're not keeping up with your sales, that is a recipe for disaster," Butterton said.
Yet he finds the work more personally fulfilling. He enjoys connecting with customers at events, adapting live-stream formats on the fly, and applying his engineering skills—like laser-engraving customized bottle openers to attract first-time buyers.
The Flop That Sparked a Pivot: Cutting Boards
Not every idea stuck. Butterton once tried crafting and selling wooden cutting boards but quickly realized he was entering an oversaturated market against artisans with superior skill and efficiency.
"I'm not super great at woodworking, and there are a lot of people that are really good," he said. "It takes me longer, I can't sell my products for as much, and the return on investment was just not there."
That experience crystallized his business philosophy: *During a gold rush, be the one selling shovels—not digging for gold.*
Rather than compete directly, he pivoted to a complementary product: a food-safe wood finish formulated with hemp oil, white beeswax, carnauba wax, candelilla wax, and orange peel oil. The economics improved dramatically—he could produce 50 cans per hour at ~$5 each and sell them for $15.
He built a website for the brand, One-Eyed Willy's, and began selling at trade shows and online. While the venture never scaled like his ATM or card businesses, it reinforced a valuable lesson in strategic positioning.
The Balancing Act Ahead
After testing multiple ventures, Butterton is now considering consolidation: "If I remove one and put that much more time into the other, could I make even more?"
For now, he continues to balance his government engineering role, family responsibilities, and a diversified portfolio of side projects—constantly evaluating which endeavors deserve more focus and which are simply worth maintaining.
His journey reflects a pragmatic approach to entrepreneurship: start small, validate quickly, learn from failures, and double down on what works—all while protecting the stability that lets him take smart risks in the first place.