Stepping into Ivana Trump‘s Manhattan townhouse, with its limestone facade and embellished gold entryway, is like stepping back in time to the 1980s, when the late socialite and her ex-husband, former President Donald Trump, were the ultimate power couple. The home’s décor—leopard print, pink marble, crystal chandeliers and lots and lots of gold—is reflective of the glamorous, over-the-top aesthetic that helped define that era and the Trump real-estate portfolio.

“My mom absolutely loved that house,” said their son Eric Trump, noting that it reflected her “style and elegance.” The opulence, he said, “embodied Ivana Trump.”

Ms. Trump’s estate is now putting the property on the market for $26.5 million following her death earlier this year, Eric Trump said. Ms. Trump was found dead at the home in July. The proceeds of the sale are slated to go to her three children: Donald Trump Jr., Eric Trump and Ivanka Trump.

Ms. Trump purchased the townhouse for about $2.5 million in 1992, the same year her divorce from Donald Trump was finalized, records show. While Ms. Trump also had homes in Florida and France, Eric Trump said the New York property was especially important to her. “She was so comfortable there,” he said. “It was the last possession in the world she would ever have gotten rid of.”

On a recent Tuesday, Ms. Trump’s tiny Yorkshire terrier, Tiger, greeted visitors at the door of the roughly 8,725-square-foot townhouse, which is located between Fifth and Madison avenues. Since Ms. Trump’s death Tiger has remained in the house with Ms. Trump’s longtime assistant, to whom he is attached, Eric Trump said.

The entrance hall has blood-red carpets, upholstered fabric walls in red and gold, lashings of pink marble, a crystal chandelier and a Romanesque statue. The upper floors are accessed by an old-fashioned birdcage elevator and a red-carpeted, curved marble staircase with a painted mural.

In her 2017 book, “Raising Trump,” Ms. Trump described her design style as “luxurious” and “whimsical.” When she bought the house, she wrote, it needed significant work. No one had lived there for about 12 years, and the property’s last incarnation had been as a dentist’s office, with many small rooms.

The second floor now has two formal entertaining areas. At the front is a living room heavily upholstered in shades of red and green, with a pleated gold fabric ceiling and velvet chairs. The space is decorated with ornate figurines and other collectibles, such as clocks and silver jewelry boxes. In her book, Ms. Trump described the room as “how Louis XVI would have lived if he had had money.”

The dining room has walls covered in gold fabric and a chandelier hanging above. Two tables, one round and one long and rectangular, have tall-backed chairs upholstered in golden yellow. Eric Trump said the furniture could be negotiated with the sale of the property, should a buyer be interested.

In between the two rooms stands a white grand piano. While Ms. Trump never played piano herself, she wrote, she had professional pianists come to entertain guests at parties. Eric Trump said his sister also played the piano.

On the third floor, there is a library outfitted almost entirely in leopard print, with spotted wallpaper and upholstery. On the walls hang a painting of two leopards playing and a framed photograph of Ms. Trump embracing a young Ivanka. Where there isn’t animal print, there’s gold. On the sofa rests a doll modeled after Ms. Trump, with blond hair, an embellished silver jacket and a fur stole.

​The primary bedroom embodies Ms. Trump’s self-described whimsical aesthetic. The color palette is muted pinks, greens and gold. A canopy bed sits in front of a gold-embossed fireplace. On the walls are Chinese-style murals. The en-suite bathroom is a burst of Pepto Bismol-pink, from the marble floors to the double sinks to the bathtub to the cabinets and the walls. The faucets and hardware provide accents of gold. Then, there’s the closet. In her book, Ms. Trump described it as so large that it seems to go “on, and on, and on.”

“I call it Indochine, because by the time you get to the end of it, you might as well be in another continent,” she wrote.

In the rear of the house, there is a south-facing garden and a terrace off the primary bedroom, which gets plenty of light in the midmorning and early afternoon.

“She used to go out on the private balcony every morning with coffee and she’d read the paper,” Eric Trump said.

Eric Trump said he and his siblings lived in the house during their teenage years. He has happy memories of the family chatting around the dining room table and of his mother’s parties, which at times included famous actors and even royalty, he said.

At one point, Ms. Trump converted Donald Trump Jr.’s former bedroom into a gym. From there, she could see into the house across the street, where fashion designer Donatella Versace lived, Eric Trump said. She would wave to Ms. Versace from the treadmill. “They loved each other,” he said.

The five-story, 20-foot-wide house is currently configured with five bedrooms, but could be redesigned to accommodate more, according to the listing agents, Adam Modlin of Modlin Group and Roger Erickson of Douglas Elliman. Two of the floors are currently split into several rooms, but those spaces could be combined to take advantage of the full width of the townhouse, the agents said.

The one conspicuously absent amenity: a full-size kitchen. There are two small, galley-style kitchens, one off the dining room on the second floor and another by a study on the garden level. Ms. Trump, by her own admission, didn’t cook much in her later years. The agents said a buyer could likely build a larger kitchen on the garden level.

The agents said most prospective buyers will want to do a significant renovation. Eric Trump said his mother once had plans drawn up to construct a pool in the basement, which already includes a sauna, but changed her mind.

The block is one of the city’s most illustrious, according to the listing agents. In addition to the Versace mansion, now owned by hedge funder Thomas Sandell and his wife Ximena Sandell, the street has drawn big names like billionaire Len Blavatnik and record mogul Tommy Mottola, according to public records and people familiar with the properties.

“It’s like being between Boardwalk and Park Place on a Monopoly board,” Mr. Modlin said.

The Trump property comes on the market as New York’s townhouse market revs up. In recent months, a series of major Upper East Side townhouse deals have closed, despite what agents say is a cooling market for luxury homes across the country. They include the $50 million sale of a Beaux-Arts mansion that was owned by the Permanent Mission of Serbia to the United Nations, and the $48 million sale of real-estate investor Keith Rubenstein’s townhouse.

Ms. Trump, a onetime model, hailed from the former Czechoslovakia. While married to Mr. Trump, she took on several roles at the Trump Organization, including vice president of interior design. She also supervised construction and design of Trump Tower and the Trump Plaza Hotel. Later, she had her own fashion line.

“She wasn’t a, ‘Let’s throw on a pair of sweatpants,’ kind of person,” Eric Trump said. “She believed in looking good.”