Lauren Santo Domingo's apartment was featured in Vogue.

It might sound like a fortune to mere mortals, but the $5.5 million fashion “It” girl Lauren Santo Domingo and her billionaire husband just pocketed from selling their fancy Manhattan apartment that once appeared in Vogue is small change to the uber-wealthy socialites.

After all, while she runs Moda Operandi, which sells couture clothes days after they’re seen on the catwalk, Colombian beer heir Andrés Santo Domingo is worth $5.2 billion, making him the 354th richest person in the world, according to Forbes’ latest ranking of billionaires.

The couple first listed their full-floor, three-bedroom apartment in Manhattan’s Flatiron district for sale for $7.25 million in February 2016 and cut the price several times, last asking $6 million. They came down by another half a million dollars to seal the deal, which closed last month.

In addition to Moda Operandi, Lauren is a longtime contributing editor at Vogue and at one point she had a column called “APT With LSD,” where she toured the fabulous homes of wealthy Americans, even featuring her own apartment, for which the couple paid $2.95 million for in 2004.

She wrote that she mainly used their huge living room for entertaining guests and decorated it with eclectic items such as a giraffe’s skull, a bronze statue of her dog, a $500,000 hippopotamus bar created by artist François-Xavier Lalanne (only eight exist), as well as works by the likes of Salvador Dalí and Andy Warhol.

The 4,713-square-foot condo complete with its own private elevator entrance is located at 31 West 21st Street, an 11-unit boutique building, where their neighbors included EMI Music Worldwide chief executive officer Bhaskar Menon, and Google executive chairman Eric Schmidt.

The latter reportedly dropped $14.4 million on a sprawling duplex penthouse in 2011 that was once used as the home of Shia LaBeouf’s character in “Wall Street: Money Never Sleeps.”

The Santo Domingos now reside at a town house next to Gramercy Park, which they bought for $18.5 million in 2009 and fully renovated. They also own a duplex apartment in the heart of Paris’s tony Saint-Germain neighborhood.