Stone Chateau in Northern N.J. Sells for US$17.7 Million, the State’s Biggest Home Sale in Three Years

A Versailles-style chateau in Alpine, New Jersey, has just been sold for US$17.7 million, the state’s highest home sale in the past three years.

The sale of the custom megamansion, which closed Tuesday, is also the highest-priced in the affluent town and in the Rio Vista neighbourhood since January 2022.

David and Mindy Kwon bought the vacant Bergen County land in 2011 for $3.95 million, according to records on Property Shark. They declined to comment on the sale.

The Kwons spent four years building their dream house, which they christened Chateau de la Roche for the boulder that had to be blasted out of the ground before the project could commence.

The interiors are by Denise Albanese, who, in her dual role as realtor associate at the Christie’s Mahwah-Saddle River Sales Gallery, also represented the Kwons in the sale.

“Among the luxury homes in Rio Vista, Chateau de la Roche is the cream of the crop,” she said. “It’s one of the most elegant—there’s a general feeling of grandeur and luxury.”

The seven-bedroom, 10.5-bath house, which was completed in 2017, is palatial enough to suit royalty.

The 25,700-square-foot house, which is about a half hour from Manhattan, has a 15-seat theatre, an elevator, a gas fireplace, a billiards room, two bars, a wine cellar, two indoor plunge pools, a sauna, a steam room, a conservatory and a central-vacuuming system.

Other features include a grand central staircase illuminated by a massive crystal chandelier, a great room warmed by a mammoth fireplace, a conservatory, a mezzanine and an ornately wood-panelled library with a fireplace. The garage can accommodate four vehicles.

On the left, palatial windows define the conservatory. While in the wood-panelled library, on the right, a fireplace adds atmosphere and warmth. David Heald Photography

Outside, there’s a resort-style swimming pool and a spa.

It’s the details, Albanese said, that set the chateau apart.

“It has soaring ceilings, custom fireplaces and bridal staircases,” she said. “In one of the powder rooms, there is glass-beaded wallpaper.”

Mansion Global could not immediately confirm the identity of the buyer, who was represented by Richard Orlando and Jason Pierce of Prominent Properties Sotheby’s International Realty and Taylor Lucyk of Christie’s International Real Estate Group

Albanese said that the Kwons, who own several other homes, are downsizing.

The transaction, she said, was a “full-circle moment for me as an interior designer and real estate agent. It’s a little sad to see the chateau go, but I’m already working with the sellers on their next interior design and real estate venture.”

Kwon is the corporate vice president and chief legal officer of ADP (Automatic Data Processing), a Roseland, New Jersey., company that provides human resources management software services. And he’s a trustee on the board of SEEDS, a New Jersey-based nonprofit that helps high-achieving students from low-income families.

Chateau de la Roche was originally put up for sale in 2021 for $25 million. Since 2023, the asking price has been $22.49 million.

Australia’s major CBD office markets are recording some of their strongest rental growth since the pandemic, with businesses increasingly prioritising premium office space despite elevated geopolitical and economic uncertainty.

Knight Frank’s Australian Office Indicators Q1 2026 report found net effective rents in Sydney and Melbourne CBDs rose at their fastest annual pace since COVID-19, increasing 10.2 per cent and 6.8 per cent respectively over the 12 months to March.

Brisbane posted the strongest growth nationally, with net effective rents climbing 11.7 per cent over the same period.

The report points to a widening divide between prime CBD office towers and secondary office stock, as occupiers increasingly focus on quality, location and workplace amenity when making leasing decisions.

Knight Frank Senior Economist, Research & Consulting Alistair Read said demand remained heavily concentrated in premium assets within core CBD precincts, helping drive stronger rental growth in top-tier buildings.

“Occupier demand continues to be heavily concentrated in the most desirable CBD precincts and the highest-quality buildings, accelerating a sharp divergence between core and non-core markets,” Mr Read said.

According to the report, Sydney’s Core precinct and Melbourne’s Eastern Core significantly outperformed broader CBD markets over the past year.

“In Sydney’s Core precinct and Melbourne’s Eastern Core, net effective rents surged 14.3% and 16.1% over the past year, significantly outperforming the rest-of-CBD precincts,” Mr Read said.

The rental gap between prime and non-prime office locations has also continued to widen sharply.

“As a result, core CBD rents are now 54% higher than non-core locations in Sydney and 93% higher in Melbourne, highlighting the growing premium placed on amenity, accessibility and workplace quality,” he said.

Knight Frank said the strong rental growth across the major CBDs was being underpinned by a limited supply pipeline, with few new office developments expected to be delivered in the near term.

Mr Read said subdued construction activity was likely to support ongoing rental growth and tighter vacancy rates over the medium term, particularly for premium office towers.

“The combination of sustained demand and declining levels of new development will aid ongoing prime rental growth and lower vacancy rates over the medium term, particularly for best-in-class assets,” he said.

The report noted that current economic conditions were making new office developments increasingly difficult to justify financially.

“Economic rents remain well above expected market rents, making the construction of new office towers largely unviable, and concentrating tenant demand into existing buildings,” Mr Read said.

While suburban office markets generally remained subdued compared with CBDs, Melbourne’s Southbank precinct was identified as a relative outperformer, recording annual net effective rental growth of 2.7 per cent.

The report comes as broader Asia-Pacific office markets continue to stabilise following several years of disruption linked to hybrid work trends, inflation and rising interest rates.

Knight Frank’s separate Asia-Pacific Q1 2026 Office Highlights report found Sydney and Brisbane were among the strongest-performing office rental markets in the region, behind only Bengaluru and Tokyo for annual prime net face rental growth.

The Asia-Pacific report also found 18 of the 24 cities monitored across the region recorded stable or increasing rents in the first quarter of 2026, even as geopolitical uncertainty intensified following escalating conflict in the Middle East.

Stone Chateau in Northern N.J. Sells for US$17.7 Million, the State’s Biggest Home Sale in Three Years

The custom megamansion is located in the affluent town of Alpine, not far from New York City.

Office rents in Sydney, Melbourne and Brisbane are climbing at their fastest pace since the pandemic as tenants compete for premium CBD space amid tightening supply.