Super-private deals for mansions, art, and classic cars give new meaning to the concept of 'quiet wealth'.

• Wealthy buyers and sellers are increasingly opting for private sales and off-market listings, according to auction companies and luxury real estate brokers.
• Despite a 19% decline in combined public auction sales for Sotheby's, Christie's, and Phillips last year, private sales at Sotheby's increased by 4%, and those at Christie's rose by 5%.
• "Today, discretion is crucial. People can purchase without being watched by the entire world," stated Shelby Myers, the global head of private sales for RM Sotheby's.

The original article was published in CNBC's Inside Wealth newsletter with Robert Frank, providing a weekly guide for high-net-worth investors and consumers. To receive future editions, subscribe and have them delivered directly to your email inbox.

According to experts, the wealthy have elevated the concept of "quiet wealth" by investing in private purchases of mansions, art, and classic cars to avoid public attention.

Wealthy buyers and sellers in the art world are increasingly opting for private sales and off-market listings to avoid public scrutiny on social media. Despite a decline in public auction sales, private sales, conducted discreetly between buyers and sellers, are on the rise.

Despite a 19% drop in combined public auction sales for Sotheby's, Christie's, and Phillips last year, private sales rose by 4% at Sotheby's and 5% at Christie's, totaling $2.4 billion across the two auction houses. In February, CNBC reported that Christie's sold a Mark Rothko painting for over $100 million to hedge-fund billionaire Ken Griffin, even as public auctions continued to decline.

Private sales of classic cars, particularly the most valuable and rare models, are on the rise. RM Sotheby's, a well-known classic-car auction company, has been selling trophy Ferraris, Porsches, and other high-end cars through public auctions for over three decades. However, their newly established private sales division has experienced a significant increase in sales over the past four years, with a quadrupling of sales, according to Shelby Myers, the global head of private sales at RM Sotheby's.

Nearly a third of revenue in the car industry comes from private sales, where cars are brokered between buyer and seller without an auction or public price, according to him.

""People value discretion in their transactions today, as they can purchase items without being watched by the entire world," Myers stated."

The increase in private sales for classic cars, art, and other markets is being fueled by social media, technology, and declining prices for collectibles. When a piece of art or classic car is put up for auction, the results and sometimes the seller are widely publicized on social media and blogs.

Experts advise sellers to avoid putting a valuable item up for auction and risking its failure in public.

"No one wants it to be public when someone loses money on a sale, as it has become very public now, Myers stated. Unlike a few years ago, buying a car at auction used to keep prices private and not be splashed all over social media."

Collectors who enjoy exhibiting their cars at events and award shows are increasingly avoiding auctions because viewers are more likely to determine the price the owner paid.

"The car enthusiasts were once a small and tight-knit group," Myers stated. "Now, when a major collector displays their car, it quickly spreads across blogs and the internet. Everyone can easily identify the owner and the amount they paid."

In Manhattan, Malibu, Aspen, the Hamptons, and Palm Beach, many of the largest real estate deals are now being made through private or "off-market" sales. These properties, also known as "whisper" or "pocket" listings, are not publicly listed on multiple listing services or websites but are discreetly marketed to a select group of brokers and buyers.

In Manhattan's Greenwich Village, a townhouse was sold for $72.5 million in an off-market deal, making it the most expensive townhouse ever sold downtown. In Palm Beach, a 13,000-square-foot mansion was sold off-market for $60 million, making it one of the most expensive non-waterfront homes ever sold on the island. In Aspen, the first sale over $100 million was an off-market deal between billionaires Steve Wynn and Thomas Peterffy, with the broker representing both the buyer and seller.

Since the 1980s and 1990s, off-market deals have originated in Los Angeles as a way for celebrities and movie stars to evade the attention of overzealous fans who would frequent their listed homes.

Over time, wealthy sellers in Los Angeles have joined the off-market craze, according to Douglas Elliman real estate agent Ernie Carswell.

Carswell stated that even the average multi-millionaire or billionaire enjoys the concept of selling without media intrusion and privacy violations.

Carswell has a billionaire client in New York who wants a special property in Los Angeles, so he is considering a mega-mansion owned by a Middle Eastern billionaire who is only offering it to select buyers. Additionally, Carswell is working on a deal in Palm Springs with a celebrity selling a home he didn't want to be publicly shown to a billionaire buyer who doesn't want any photos of his new home on the web.

"Carswell stated that they do not want burglars to know how to access the bedroom, the size of the land, or how to navigate through the hedges. He attributed this to technology."

According to Carswell, off-market listings are not suitable for properties under $5 million because they have a larger pool of potential buyers and can benefit from broader marketing. However, for special mega-homes in Malibu, Bel Air, or Beverly Hills priced over $20 million, the pool of potential buyers is smaller, and most are already known to the brokers, making an off-market agreement more appealing.

Carswell emphasized the significance of broker relationships, particularly for the wealthy.

The value of a skilled and connected real estate professional has never been more crucial, particularly at the high end, he stated.

Some brokers argue that sellers who opt for a private sale may not receive the highest price for their expensive properties because they limit their potential buyer pool.

"Noble Black, a real estate broker at Douglas Elliman, stated that his clients are leaving money on the table by not listing their properties. He explained that while privacy and discretion are valid reasons for not listing, they come at a premium cost."

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