So, you have a brilliant business idea, but not a ton of money to get it in motion — what do you do?

Well, "Million Dollar Listing" star and real estate powerhouse Ryan Serhant says he gets this question a lot — and his answer might actually surprise you.

"People think that they need money, like start-up capital, to start a business," he explains, "which sometimes is true, but really isn't always true."

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(Does he have your attention yet?)

"I like to answer this question with what I call the '3 fences,'" Ryan continues, referring to the hurdles he reveals how to overcome in his book Sell It Like Serhant.

So, let's hear 'em!

1. Hurdle: Lack of Money

How to Overcome: Use Your Voice (it's free!)

Ryan started his business the day Lehman Brothers filed for bankruptcy in 2008, he tells us.

"I had no money," he explains, "but what I did have was a voice to tell people what I did. And that, honestly, today for everybody is social media."

In fact, Ryan still uses social media to his advantage to this day.

"It's that number one free marketing device," the real estate expert says.

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2. Hurdle: Competition

How to Overcome: Do What Your Competitors Aren't Doing

Standing out from the competition can seem daunting, but Ryan thinks separating yourself is actually quite simple.

"Do what they don't do," he tells us, "which is take the time to promote yourself with something interesting and fun."

For instance, in the fall, he suggests handing out free pumpkins. (Free stuff is the way to anyone's heart, right?)

"No one else is doing that because they're too busy," Ryan explains. "[But] every new person you meet is a new contact you have that the competition doesn't have."

3. Hurdle: Lack of Positivity + Motivation

How to Overcome: Give Yourself a Future Reward

Treat yourself like a kid and give yourself a future reward for all the hard work you're putting in.

"Plan a vacation, even if you can't afford it right now," Ryan suggests. "Put it three, four months — maybe six months — off into the future."

And circle it in red on your calendar so you never forget about it!

"You will work so much harder subconsciously to pay for that future vacation," he says.