When Barbara Corcoran sold her company for $66 million, she didn't know how much it was worth—here's how she negotiated anyway

Barbara Corcoran says the "biggest negotiation of her entire life" came from pure luck.

The millionaire investor on ABC's "Shark Tank" recently took to TikTok to dish about selling The Corcoran Group, a real estate firm she founded at age 23. Nearly three decades later, she flipped it to brokerage firm NRT for $66 million.

The large dollar figure wasn't the result of industry research or market valuation, Corcoran said: Rather, it was her "lucky number."

"I figured my business had to be worth something," said Corcoran, now 74. "After all, we were making money. But what it was worth, or how the heck to figure it out, I had no idea."

Corcoran wanted to sell her company because she'd achieved her goal: The Corcoran Group was the largest brokerage in New York, she said. "There was nowhere else to go," she added.

So she hired a "big-shot attorney" to help her broker a deal, she said. His first question for her: How much money do you want? "Whatever you can get," Corcoran responded.

Perhaps predictably, that's not the wisest approach, experts say. Negotiations are often won through preparation — knowing exactly what you want and which alternatives you'd still consider a success, Harvard Business School research associate Katie Shonk wrote in a university blog post in March.

Still, Corcoran forged ahead. After three days, her attorney returned with a $22 million offer from NRT, said said. She couldn't believe how much money it was, she added.

As a negotiation tactic, she rejected the offer, waited three days, got back on the phone and demanded "$66 million dollars, and not a penny less," she said. "I was acting like the big deal I knew I wasn't, and I hung up."

NRT agreed to the dollar figure the next day, Corcoran said.

Today, NRT is known as Anywhere Advisors. Its parent company, Anywhere Real Estate, has a market cap of $660.98 million, as of Tuesday morning.

It's unclear whether Corcoran could have gotten more for her company, given its then-status as New York's top brokerage. The Corcoran Group's primary competitor at the time, Douglas Elliman, sold for $75 million four years prior, The New York Times noted.

To Corcoran, it didn't matter: The sale represented a huge return on her decades of time and work invested, and taught her a valuable lesson about negotiating.

"Negotiation has more to do with good timing than money," she said.

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

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