Updated

During summer 2014, New York City yoga studio owners Raquel Vamos and Dov Vargas created a rudimentary website for $35 to sell a plastic wheel they invented to help with deep back stretches. At most, they expected to get a few dozen orders for the $99 yoga prop from friends and students. But after a few months, they were selling up to 100 Dharma Yoga Wheels a day. After a year, they’d raked in $1.3 million and garnered Instagram raves from popstress Britney Spears and a number of NFL players.

But the couple knew this was hardly cause to rest on their laurels. They understood that one product does not make a thriving company. So Vamos quit her full-time nursing job and threw herself into the business. The team then hired a seasoned marketer to help keep the company in the spotlight, and got to work creating various yoga wheel upgrades and spin-offs, including an international yoga-teacher-training program based on their invention.

“You can’t get too stale with the business,” Vamos says. “You’ve got to constantly keep creating.” In fact, she says, the best time to research how to improve a product, create accessories for it and otherwise expand your business is the moment you launch it. Vamos hopes that mindset keeps the company moving forward, with the potential to bring in $1.7 million by the end of this year.

Read more success stories about turning a hobby into a paying job here.