When the former owner of Mission De Flores closed his shops last May, it was his sixth business attempt. But in the tradition of turning lemons into lemonade, the 50-year-old Steve Rubenfaer is applying the lessons learned in trying to run a small business in San Francisco toward helping others succeed.

“I know a lot of business owners in the Mission and I feel their pain,” said Rubenfaer while sipping on tea at Muddy’s Café on Valencia Street. “There are lot of people out there who are visionaries and founders and have ideas, but they don’t know how to make it into a business.”

Take the five men running shoe shine stations at San Francisco International Airport, who wanted to become owners of the business.

“We didn’t have any slight idea about making a proposal,” said John Jesus Alberto, a new owner of SFO Shoeshine. Most of us are from the Philippines, so many of us are not equipped with the language.

Rubenfaer stepped in, interviewed the men and wrote the proposal.

Earlier this month, the San Francisco Airport Commission approved the proposal and the former employees are on their way to becoming owners. They credit Rubenfaer’s help. “All the ideas came from us, but the way he presented it was convincing and very realistic,” Alberto said. “He believes in us.”

Rubenfaer, who has lived in the Mission for 22 years and founded and closed four businesses in the city (and two outside of it), learned vital lessons about how to keep the lights on, doors open and actually make money.

Many of Rubenfaer’s current clients, who range from doll makers in Oregon to costume designers in Menlo Park, said they hired him because of his experience in the trenches of small businesses.

A handful were aware of Mission De Flores’ recent closure, but that failed to deter them from hiring him — to do everything from marketing and social media campaigns to bookkeeping and funding. Instead, many of his clients are impressed and can relate to his long startup history.

Trennee Zweigle owns Buddys 4 Kids, where a group of Oregon nurses  handcraft dolls for children experiencing serious illness or trauma. She hired Rubenfaer to help her find funding and keep the business afloat.

“He said, ‘Don’t ever give up, you’ve got this’” Zweigle said. “He’s kind of been there, done that.”

Rubenfaer, who opened Mission de Flores in 2013, survived and expanded the business after his partner, florist Zekiel Steffens, committed suicide about a year after they opened.

On his own, he transformed the small shop on Folsom Street into a floral conglomerate and brand, providing flowers for big events and even landscaping and plant care. He also opened an additional shop in the Excelsior and a kiosk on 20th and Valencia Streets in 2016.

But Rubenfaer closed the shop for good last May. “We just never made it profitable,” he said.

Before Mission De Flores, he founded an online art startup followed by an online stamp store. But his career started years before he moved to the city in 2009. When he was 14, he founded a stamp-dealing business in his hometown of Detroit, Michigan.

“He was maybe one of the youngest stamp dealers in the county,” said Leon Rubenfaer, Steve’s father. “He had a very good business sense.”

His clients seem to agree.

Mike Goedde, the chief executive officer of Suitables, a children’s costume company based in Menlo Park, hired Rubenfaer after looking at his resume and seeing how many startups he’s founded, and his expertise in social media and marketing.

After a month of working with Rubenfaer, about “100,000 people were reached through Facebook and Instagram,” said Goedde — even some celebrities.

Rubenfaer feels like he has found his calling.

“It’s been great helping people realize their dreams,” he said.

Rubenfaer hopes to work more directly with small business owners in the Mission.

“I’d rather be helping local businesses in the Mission,” Rubenfaer said. “I know what they are up against, and I know how hard it is.”