Inside a NYC $80 Million Megamansion: Cold Plunge, Garage Bar, and Wine Cellar

A historical neo-Italian Renaissance carriage house built in 1910 and later transformed into a spectacular residence by former Morgan Stanley CEO John Mack and his wife, Christy, has just hit the market in Manhattan for an astonishing $80 million.

The Upper East Side estate once served as a garage and chauffeur's quarters for Singer heir Stephen C. Clark and was later used by Paul and Bunny Mellon as a private garage. The Macks purchased the 15,978-square-foot structure for $13.5 million in 2009 and transformed it into a 20-room residence in 2011.

A "no-expense-spared renovation" now features quarter-sawn oak floors, custom wallpapers, bespoke drapery and fabrics, and designer lighting. The lavish residence has climbed its way to the top spot on the week's most expensive homes list.

Luxurious amenities include security and staff offices, a 13-seat soundproof theater, a one-car garage doubling as entertainment space, private guest quarters with a full kitchen, and a chef's kitchen with walk-out dining terrace.

Other highlights include six fireplaces, a wood-paneled library, a primary suite with dual dressing rooms and marble baths, two soundproof offices, a 6,319-bottle wine cellar with prep kitchen, and a rooftop terrace to enjoy the city views.

Wellness amenities on the lower level offer a cold plunge, steam room, sauna, massage room, and a full gym.

More spectacular estates to make the week's most expensive homes list include a brand-new mansion on Nantucket, MA, a 48.2-acre Greenwich, CT, estate, and a recently built Washington residence overlooking Lake Washington.

10. 350 Eagle Park Dr, Aspen, CO

Price: $41,500,000

La Reve: This seven-bedroom mansion was sold in 2019 to an undisclosed buyer for $9,500,000, roughly half its original asking price of $18,400,000. The seller, James Fifield, is the former president of EMI Music and The North Face.

Now listed for more than four times that sale price, the 13,919-square-foot “highly curated” residence originally hit the market for $60 million in September 2025. The 15.14-acre property atop Buttermilk Mountain is a legacy estate designed by Uruguayan architect Horacio Ravazzani “in his only North American engagement,” according to the listing. Bespoke details include African iroko wood, a 35-foot glass solarium inspired by the Louvre, a central corridor creating a gallery-inspired art setting, and a primary suite with two marble soaking tubs.

The property features direct access to trails for skiing or hiking.

Carrie Wells of Coldwell Banker Mason Morse-Aspen is the listing agent.

9. 4521 Pine Tree Dr, Miami Beach, FL

Price: $42,500,000

Redevelopment opportunity: This 1.35-acre property was purchased for $23,800,000 in December 2024 by Israeli billionaire Teddy Sagi, who planned to tear down the existing mansion and build a new 20,000-square-foot mansion.

According to the listing, his new development never came to fruition, as “the existing residence remains on the property.” Sagi does, however, have approved plans for a 25,000-square-foot estate, which are included with the sale. The proposed design features nine en suite bedrooms, a guesthouse, separate staff accommodations, and an eight-car garage. Lavish planned amenities include an infinity pool, a hot tub, a fitness center, a spa, saunas, a screening room, a sport court, and a rooftop lounge. Outdoor kitchens, patios, and covered terraces overlook a yacht dock.

Buyers should note that “construction of the proposed estate is not included” in the listing price.

Adalis Carbo of The Firm Properties is the listing agent.

8. 33 Cliff Rd, Nantucket, MA

Price: $45,000,000

Brand-new construction: This nine-bedroom compound featuring views of Nantucket Sound is tucked away in the coveted Cliff neighborhood.

Located minutes from the beach, restaurants, and shopping, the property boasts a primary residence, a detached guesthouse accessed by a private tunnel, and an in-ground pool. Highlights include a chef's kitchen with a breakfast bar and window seating, an entertainer’s dining room, a bunk room, a home theater, and a billiard room. The turnkey estate is being offered fully furnished.

There is also a two-car garage with a studio.

Robert Sabelhaus of Great Point Properties is the listing agent.

7. 51 E 80th St, New York, NY

Price: $45,000,000

Upper East Side townhouse: Built in 1899, this seven-bedroom mansion in Carnegie Hill's tree-lined neighborhood has been "meticulously reimagined over generations."

The 10,252-square-foot interior spans six floors and comes with an additional 1,885 square feet of outdoor terraces and gardens. Opulent details include European materials, high ceilings, multiple fireplaces, arched windows, custom cabinetry, and two staircases. Other amenities include a media center, a chef's kitchen with butler's pantry and marble breakfast bar, and a luxe primary suite encompassing the entire second floor with a marble soaking tub, double-sized glass-enclosed shower, and private terrace.

A "discreetly integrated yet fully self-contained" staff suite is located on the fourth floor.

Modlin Group LLC is the listing agent.

6. 114 John St, Greenwich, CT

Price: $48,000,000

Seven Bridges: This 48.2-acre property spans three separate lots and comes with a 17,000-square-foot residence, a 16,000-square-foot stone-and-glass house, and a separate 32.5-acre parcel.

Bordered by the Greenwich Land Trust, the property presents a “once-in-a-lifetime opportunity” and could be transformed into a legacy compound for multigenerational living. Built in 2009, the residences feature three fireplaces, exposed beams, vaulted wood ceilings, French doors, and floor-to-ceiling glass walls framing the scenic views.

“Both incredible homes have served as private galleries for one of the world’s most significant collections of representational art,” the listing states.

BK Bates of Houlihan Lawrence is the listing agent.

5. 917 S Mill St, Aspen, CO

Price: $49,000,000

Turnkey townhome: This four-bedroom townhouse being offered fully furnished last traded hands for $25,500,000 in 2021. It was entirely modernized in 2022.

Nestled in the new Lift 1A ski corridor, the 6,578-square-foot residence with a two-car garage features “exceptional ski access” and the privacy of a single-family home with the convenience of townhome ownership. The three-level layout offers a unique floor plan with a main-level primary suite, lower-level guest suites, and an upper level with a great room, dining area, kitchen, and office. A private elevator provides access to all three floors.

Two outdoor terraces overlook the private backyard with a hot tub.

Steven Shane of Compass is the listing agent.

4. 795 Ocean Rd, Bridgehampton, NY

Price: $58,000,000

Sagg Pond: Custom-built in 2006, this nine-bedroom waterfront estate sits on 4.5 acres comprising two parcels. It features views spanning the Atlantic Ocean.

A 9,680-square-foot “timeless” interior offers a blank canvas to display museum-worthy artwork and “meticulously curated” spaces across three levels. A two-story living room has a fireplace and walls of glass providing deep water views. The family room with a wood-clad ceiling is surrounded on three sides by windows and doors, offering a seamless transition between the indoor and outdoor living areas. Designed for entertaining, a chef’s kitchen has a marble center island, a dining area with a fireplace, and a breakfast banquette for up to 12 guests. Other highlights include a home theater, a wood-paneled library, a recreation room, and a primary suite with a dressing room and private terrace.

Outside, entertaining spaces feature covered terraces, a summer kitchen, a championship-caliber tennis court, a private boat dock, a 60-foot heated pool, and a pool cabana with a kitchen, sauna, and outdoor shower.

Timothy Davis of The Corcoran Group - Southampton is the listing agent.

3. 1285 N Ocean Blvd Lots 1 & 2, Palm Beach, FL

Price: $69,900,000

New construction: Located in the North End, this seven-bedroom British Colonial estate overlooking the Atlantic Ocean boasts 5,637 square feet of bright and airy living space.

Highlights include an elevator, a first-floor secondary bedroom, a formal dining room, a primary suite with dual walk-in closets, and a lower level offering space for a fitness center or wine cellar. Other amenities include a heated saltwater pool with a spa, a two-car garage, and covered loggias overlooking the pool.

The oversized lot also offers the opportunity to build an additional 5,000-square-foot structure, according to the listing.

Elizabeth DeWoody of Compass Florida is the listing agent.

2. 3600 Hunts Point Rd, Hunts Point, WA

Price: $71,000,000

Private compound: This six-bedroom estate anchors a 2.33-acre lot and features spectacular views of Lake Washington. It is said to be owned by Aegis Living CEO Dwayne Clark.

The 18,995-square-foot residence was recently built and hit the market days after Clark announced his plans to step down and move to Arizona. The sprawling home, “inspired by the timeless estates of Europe,” is surrounded by outdoor entertaining spaces and extensive wellness amenities.

An in-ground pool also has stunning lakefront views.

Jay Kipp of Realogics Sotheby's International Realty - Downtown Seattle Belltown is the listing agent.

1. 165 E 70th St, Manhattan, NY

Price: $80,000,000

Neo-Italian Renaissance carriage house: This five-story residence has been entirely reimagined and now offers a sophisticated 15,978-square-foot interior.

The estate is said to be owned by John Mack, former chief executive officer of Morgan Stanley, and his wife, Christy, who bought it for $13.5 million in 2009 and transformed it into a luxury home. Found throughout the six-bedroom residence are security and staff offices, a 13-seat soundproof theater, private guest accommodations, a glass-enclosed dining room, a mahogany-paneled library with a fireplace, and a primary suite with dual dressing rooms and marble baths. Other lavish amenities include an irrigated terrace, a playroom, a study, two offices, and a 480-square-foot rooftop terrace with custom landscaping.

A double-height lower level features a wellness retreat with a cold plunge, steam room, sauna, massage room, and full gym, along with a 6,319-bottle wine cellar and a prep kitchen.

Mike Fabbri of TRIP - The Agency REBNY is the listing agent.