This $26 million San Francisco mansion a block off Billionaires’ Row gained’t promote. Why?

One of the most expensive homes listed in San Francisco features panoramic views of the North Bay, a seven-vehicle “motor court” and an elevator accessible on each of the mansion’s four floors.

With a listing price of $25.8 million, the 118-year-old corner mansion at 2698 Pacific Ave., that sits a block away from the city’s Billionaires’ Row, has only been home to fewer than a half-dozen families since it was originally built in 1904. It first belonged to a wealthy oil magnate. Decades later, the property one block north of Alta Plaza Park came into the hands of the doctor who founded orthomolecular medicine.

The mansion’s extravagant visuals — from the second-floor “green room” that features gold ceiling accents and a chandelier to the third-floor bathroom with pearl ceramic sinks — make it an “Instagram dream,” Herman Chan, the owner’s agent, said. “Every room is a different backdrop.”

The portico entrance’s ornate overhead is encrusted with detailing.

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No corner of the mansion is spared from lavishness — even the dog wash in its fourth-floor laundry room is coated with navy blue marble tiles.

Yet, the nearly 11,000-square-foot mansion has been on the market since December 2019, according to Zillow. The prolonged listing shows the complexities around how the pandemic has affected the sales of high-end, luxury homes.

Throughout the nation, sales of these lavish properties increased during the pandemic, with listings site Redfin showing a 60% increase in luxury home sales from 2020 to 2021. The jump in those sales is largely attributed to people wanting more space or privacy during a pandemic , but it also illustrated how the wealthy were still spending at a time of economic uncertainty for many Americans.

Yet, in San Francisco the sale of luxury homes (defined by listings of $4.5 million or more) increased by “only” 31% during that same time frame. Meanwhile, the median sale price for luxury homes in San Francisco decreased by 3.2%, the only city among the nation’s 49 most populous with a decline in that category. (New York City was excluded in the data.)

“There has been a little bit of a reticence” from buyers, Chan said. “A lot of that can be attributed to the pandemic. For the past year, I think people who are ultra, ultra high net worth are exploring other cities.”

The grand staircase is a soaring, stately feature suitable for making a grand entrance.

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Through the market fluctuations, the mansion at 2698 Pacific Ave. remained unsold — though not for lack of attention.

A video tour of the mansion by a popular real estate YouTuber has more than 1 million views with thousands of comments from viewers who admired its “breathtaking” interior designs.

The owner’s agents regularly field booking requests. Influencers drawn to the mansion’s exorbitant backdrops want it to be the site of their next photo shoot. Couples looking to celebrate their nuptials in grand fashion want to walk down the mansion’s third-floor grand staircase. Startup companies hoping for a big fundraising haul want to court donors with its palatial excess.

Most requests are turned down politely, Chan said, though a movie production company of a “major Hollywood star” is tentatively scheduled to film a scene at the mansion this summer.

About a dozen members of that film’s production crew recently toured what was once called the “Mack Mansion” — named after Julius Mack, the oil magnate and financier whom the estate was initially built for by the famed father-son team Newsom & Newsom. The film crew became enamored with the home’s top-floor views of the bay, Chan said.

The view from the roof patio of the penthouse suite at 2698 Pacific Avenue is one of the selling points of the $25.8 million mansion.

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Much of the mansion’s recent fanfare came after it hosted the prestigious Decorator Showcase in the spring of 2017. A team of 28 elite interior decorators descended on the mansion, each picking a room in the home to renovate. A second-floor bathroom now features all-black walls with turquoise tiling and a marble sink with gold faucets. The library room across from the mansion’s green room includes modern, orbital-like light fixtures with a wood-beam ceiling.

The interior designs, much of which remain in place, wooed the current owners, who no longer live in the home. They purchased the mansion for $16 million in fall 2017 after attending the Decorator Showcase earlier that year.

Now, they’re asking $25.8 million for the next owner, a price Chan said is in line with another luxury mansion on the market that hosted the 2019 showcase.

A bathroom in the penthouse features a panoply of designer touches.

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The Mack Mansion and its elegant backdrops have drawn a following on social media over the years. The property, however, has been on the market since before San Francisco’s first shelter-in-place orders.

Though there’s no single answer as to why, Chan said the pandemic likely has played a prominent role.

But, Chan said, “there’s still an appetite for beautiful, beautiful properties, especially for legacy families in the Bay Area.”

Ricardo Cano is a San Francisco Chronicle staff writer. Email: ricardo.cano@sfchronicle.com Twitter: @ByRicardoCano