Million Dollar Listing star Ryan Serhant reveals his most difficult sale

Even celebrity real estate agents have bad sales days, difficult clients and deals that just do not seem to come together.

Rising to fame selling luxury apartments on the Comcast  (CMCSA) - Get Free Report-owned Bravo series "Million Dollar Listing New York," star broker Ryan Serhant revealed how a buyer for an $8 million apartment "gave [him] a runaround for almost a year" when he was just starting out.

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"Even when I did my first deal and we found the buyer in another country, [...] he gave me a runaround for almost a year," Serhant told TheStreet in an exclusive video interview. "Never sent that deposit. People started [the deal.] It was litigation. It was crazy. And then one day an $830,000 deposit shows up from a state controlled-bank and everyone was excited."

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New York real estate rules are unique compared to the rest of the country in that co-ops will require approval from the building's board before purchase (someone with the money can still get rejected by the board.) Serhant recalled how the buyer refused to complete the approval application and kept reappearing only to ghost again.

"So I got on an airplane and I went and I found him and I never met him before," Serhant said. "He was a really intense guy and I got him to do somewhat of the application. And then I came back and he disappeared again."

Serhant explained that his team had assumed the buyer was "totally dead" and had almost given up on the sale when he suddenly reappeared again out of nowhere "ready to close." Fortunately, they did but with a fair amount of stress.

"One day randomly, he shows up after we thought the deal was totally dead with a fleet of armored Escalades [a Cadillac  (CADIF) - Get Free Report car] getting off his private 737 and said, 'I'm ready to close now,'" Serhant recounted. "Then he just wanted to take a selfie and that was probably where I got gray hair. That deal. New York is a wild place to do business."