'Shark Tank' star Barbara Corcoran says the best investment she ever made cost $360

Barbara Corcoran, founder of The Corcoran Group and "Shark Tank" investor
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Having grown up in a working-class New Jersey family with nine siblings, Barbara Corcoran starting working from a young age. By age 23, she had already worked 22 jobs, and her latest gig was a secretarial position for the Giffuni Brothers' real estate company.

While she was working for the Giffunis, Corcoran's boyfriend at the time fronted her $1,000 to start a real estate firm, she tells Guy Raz on the NPR podcast, "How I Built This": "He said to me, 'With your personality, Barbara, you'd be great at real estate sales.' I said, 'OK, I'll try it.' … The only person I knew was Mr. Giffuni, and I asked him if he would just let me rent one of his apartments."

Giffuni gave her a listing to try to rent for $330 a month. "It was a dungeon," she recalls. "He gave me the worst one. Maybe it was a challenge. Maybe nobody could rent it. Who knows."

Regardless, Corcoran rented it for $360 a month, meaning she took home a $360 commission check, she tells Raz: "I made exactly what the monthly rental was."

What Corcoran did next was the "smartest thing I could have done," she says: "I collected that check from Mr. Giffuni, I cashed it at Citibank and I ran right over to Bergdorf Goodman and I blew it on a new coat."

It allowed her to dress the part and to project confidence in the cutthroat real estate industry. Before that first deal, "I dressed like a poor kid from Edgewater," says Corcoran.

She turned that initial $1,000 loan into a six-billion-dollar business and, she says, the coat helped. "I bought the fanciest damn coat: brown and white herringbone with real pearl buttons. Three-quarter length with fur. Real fur, not fake fur. And I wore that coat for the next three years.

"It was the smartest thing I could have done with the money because, in it, I felt powerful."

Corcoran, who now stars on ABC's "Shark Tank," was onto something. As research shows, when employees wear nicer clothes, they achieve more.

Disclaimer: CNBC owns the exclusive off-network cable rights to "Shark Tank."

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