"I work for free every day until I actually sell something," he says. "If someone wants to see apartments for 10 years, I show them apartments for free for 10 years."
He says this concept has taught him "how to build relationships based on giving things for free until you get what you want." In the end, he says the good you give out "will always come back to you, because you will be the person who never asks for a single thing."
The 34 year old's idea of giving before receiving has paid off in his career and brought him a lot of long-term success. Last year, his team at New York real estate firm Nest Seekers ranked No. 5 in the U.S. in terms of sales volume, with more than $600 million in transactions.
He tells CNBC Make It that looking back on his career, even he is sometimes surprised by the success he's reached today. He entered the business in 2008 when the housing market was collapsing and many brokers were leaving the industry. In his first year as an agent, he made only $9,000. But rather than quitting, Serhant stuck it out and embraced the struggles that came with the economic crisis.
"Never in my wildest dreams did I think that 10 years later I would do [$100 million] in deals over spotty Wi-Fi while on a safari in South Africa like I did last week," he told CNBC Make It in April.
Billionaire Charlie Munger, vice chairman of investment firm Berkshire Hathaway, has a similar philosophy. In a 2007 USC Law commencement speech, Munger told students that one of the core principles that has led to his success is understanding that "the safest way to try and get what you want is to try and deserve what you want." He explained that in order to show you're deserving of something, you have to give before you receive.
"By and large the people who have this ethos win in life, and they don't win just money [or] just honors and emolument," Munger told the law students. "They win the respect, the deserved trust, of the people they deal with, and there is huge pleasure in life to be obtained from getting deserved trust."
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