The entrepreneur, who shares the home with his wife, Sarah, purchased the first set of condos in the Millennium Tower building at 101 West 67th St. in 2005 for $7.9 million, according to property records.

“They opened the door for us and my jaw dropped,” said Mr. Gartner of the striking views and expansive living room in the original unit. “We made an offer on the spot.”

The third condo was purchased in 2006 for $1.3 million. Combined, the penthouse measures nearly 6,000 square feet.

Most of the costly finishes were in place when Mr. Gartner bought the property, including the Hebron marble used throughout the condo and the striped ironwood and maple floors in the living room. The most significant changes were done to the third unit, which was transformed into a large office space.

Using switches from his desk, Mr. Gartner can lock the office doors, warm the floor under his toes and change a glass door from transparent to opaque when he wants privacy. “It’s very nifty,” he said.

Mr. Gartner spends most of his time in the office, but he says one of his favorite rooms is the library, which is outfitted with leather floors and kewazinga wood sourced from a tree in Africa. The wood was specially chosen, purchased and shipped to the city for the room.

The home, which has eight bathrooms and two kitchens, is full of contemporary furnishings. For large gatherings, Mr. Gartner uses the living room, which holds a Bösendorfer grand piano.

Mr. Gartner founded three information technology advisory firms, including Gartner Inc. in 1979.

Part of the reason he has decided to sell the property is because it is

a little too much. A good part of the apartment is not even used,

he said. The couple also plan to spend more time at their home in Aspen, Colo., and eventually to purchase another property on the Upper West Side.

The home was initially listed for $34.5 million in September, but the price was reduced by 14.5% in December, according to StreetEasy. Prudential Douglas Elliman Real Estate holds the listing.

When asked about how it will fit the area, Ms. Glassberg said

We’re leaving the containers as they are. We feel when we cover the trim around the edges, it’s just going to look like a modern house

Panels were removed to make the doors, and lots of windows give the narrow space an open look. The construction uses the latest in green materials and technology: with the help of BNIM Architects, the house is using geothermal heat, soy foam insulation and bamboo flooring.

The container house is in the middle of a traditional block filled with bungalow homes.

(Neighbors are) always out watching. Sometimes we can’t get any work done because they want to talk about it. But all in all, we’ve had good reactions,

Glassberg said.

The house was built in about five months. It’s more than 2,000 square feet in area, has two bedrooms and a large office in back.

We love it. It’s great space for living, great for entertaining,

Glassberg said.

Debbie is a former toy accessory designer who hopes to make container houses the government could use for natural disaster victims, colleges could use for dorm space, and neighbors could use to expand existing homes.

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via Freshome.com – Interior Design & Architecture Newsletter