John Legend and Chrissy Teigen are selling their New York City home for a cool $18 million.

Located in Manhattan's chic Nolita neighborhood, the property at 374 Broome Street – a building known as the Brewster Carriage House – consists of two adjoining penthouses, which the couple originally planned to combine, but never did. Legend and Teigen bought one of the units in 2018 for just over $9 million, and the other in 2020 for $7.7 million.

Combined, the units have an interior footprint of more than 6,100 square feet, occupying the building's full sixth floor, and part of the fifth floor. They also come with an additional 3,300 square feet of private outdoor space, including a landscaped rooftop deck with its own irrigation system and gas grill.

Listing agent Noble Black tells CNBC Make It that if both units were combined, the duplex would have a total of six or more bedrooms and six-and-a-half bathrooms. The couple would also consider selling each unit individually, he says.

"The views are phenomenal and the space is completely private," Black says. "The apartment is a study in contrasts, seamlessly blending the old with a new modern, industrial aesthetic."

Built in 1856, the landmarked 19th-century building was originally a factory for a luxury horse carriage company called Brewster and Co., whose clients included notable New York City families like the Vanderbilts, Astors and Fricks.

After a fire in the 1950s and decades of neglect starting in the 1970s, the building was reportedly falling down. In 2005, filmmaker-turned-developer Ross Morgan bought the 26,000-square-foot building for $9 million and began a condominium conversion, according to the Real Deal.

In 2012, the building was converted into its current setup with nine residential units. The building also has a part-time doorman.

Other amenities for Teigen and Legend's duplex unit include include three gas fireplaces, 12-foot-high ceilings, multiple skylights, a 133-inch projection screen, heated floors in the bathrooms and a custom wine fridge under the stairs.

As for why the celebrity couple is selling?

"We've realized that because of work and everything, we're really mostly going to be in Los Angeles," Legend told the Wall Street Journal last month. "So we're going to focus our home-building energy and renovation energy on what we're doing in L.A."

The Broome Street units aren't the couple's primary home. Rather, their main residence is reportedly an 11,000-square-foot home in Beverly Hills, California, for which they paid $17.5 million in 2020. But according to the Journal, Legend and Teigen do plan to buy another home in New York City.

They're looking for a unit that doesn't require any renovation, rather than facing the challenge of combining the two penthouse units they already own, Legend said.

According to Black, the listing has had strong interest from both domestic and international buyers – both as a primary home and as a pied-à-terre. "The layout and location lend to it being attractive to a wide range of buyers," Black says. "[It] will be fun to see who the buyer is."

Last year, Legend and Teigen sold another home: a seven-bedroom, nine-bathroom property in Beverly Hills, California, that went for $16.8 million. According to Forbes, the house didn't have enough bedrooms for the couple's large family, which includes their two children and Teigen's mother.

Both Teigen and Legend declined CNBC Make It's request for comment.

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