Whether you're flipping a property or simply looking to get the best price for your home once it's time to sell, you need to be smart about where you invest your time and resources. Not every room or feature is equally important, real estate mogul Barbara Corcoran tells CNBC Make It.

"Realize that the buyer walks in and judges that house within 30 seconds," she says. So focus on the areas that prospective buyers will see immediately.

The first thing a buyer is going to see isn't even inside the house: It's the exterior, including features like your front door, mailbox, lawn and driveway.

To ensure that your home makes a great first impression, "you want to spruce up the front entrance to your house, repaint the door, make sure the bushes look good, make sure the garden looks in order and power-wash the sidewalk and the driveway," says Corcoran.

Real estate expert Sean Conlon agrees that your home's street presence, or "curb appeal," is crucial. "Your lawn should look beautiful," he tells Make It. "Your shrubs should be nice and colorful and well taken care of. ... Your shutters and windows should look nice. When people pull up, they should go, 'I could picture myself pulling up in the evening and this being my home.'"

Curb appeal is the reason Conlon says it's even OK to spend five figures on a custom door: "When you are renovating a house, you want to find ways to make it stand out from all the other homes on the market, and what better way than having the most beautiful entrance on the block? Buyers lap that stuff up."

That said, you don't want your home to stand out for the wrong reasons, says Sidney Torres, who helps struggling property investors on CNBC's "The Deed": "You don't want to have light pollution, where the house is just so bright and it sticks out from all the other houses," he tells Make It. Rather, "I want to make sure that the house is lit almost like a candle: A nice amber light."

Focus on those kinds of details pays off: "Curb appeal is everything when you're trying to sell a home," says Torres, "because that's the first thing [buyers] see to get interested."

At the end of the day, he says, "you want them to want to come inside the house."

Don't miss: Barbara Corcoran: Here's when to buy your first home—and how to do it

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