KLEIERS IN THE MEDIA

A classically configured 10-room prewar apartment at 911 Park Avenue that has retained but reinvigorated its original bones with sophisticated finishes and an unusual modernist décor is poised to enter the market at $9.5 million.

The co-op, No. 9C, is in a 1927 limestone-and-brick building on the southeast corner of East 80th Street, in a residential neighborhood prized for its lack of hustle and bustle. The monthly maintenance is $5,447.13.

The 14-story building, one of more than a dozen gracious Park Avenue addresses designed by Schwartz and Gross, was converted to a co-op in 1952. It has just 40 residences, and like most of the units, No. 9C is reached by an elegant private elevator landing.

There are open city views from the oversize windows, which face north and east, including those in the four full bathrooms, all refurbished in 2006 when David Mann of MR Architecture + Décor was commissioned by the owners Lee and Wendy Chaikin to perform an exacting renovation that left no corner of the apartment untouched.

Only the ceiling beams, oak floors, and an impressive Traulsen refrigerator in the eat-in kitchen survived the makeover intact. Mrs. Chaikin was smitten by the commercial-grade stainless-and-glass fridge, so Mr. Mann and Joe Nahem of Fox-Nahem Associates, the decorator, worked around it.

The apartment is entered through an 8-by-24-foot gallery with Venetian-plaster walls in a shimmery espresso shade; the ceilings are just below 10 feet in height. On the north end of the gallery, a hallway opens onto the 17-by-29-foot living room, which has Venetian-plaster walls, three north-facing windows, and a working fireplace with a 19th-century French limestone mantel.

The south end of the gallery connects to the 15-by-22-foot formal dining room, which has eastern exposures and an oak herringbone floor; the fourth bedroom, off the gallery, is used as a library.

The kitchen faces east and has a multifaceted center island with a marble top, a wet bar and a built-in Viking wine cooler. The countertops are stainless steel, the stove is by Viking, and the ample cupboard space includes two pantry closets; there is a banquette nestled in a corner beneath one of the windows.

Pocket doors separate the kitchen from a three-part space shared by a playroom, a nanny’s room, and the laundry room, which has a south-facing window. There is also a full bath.

The private bedroom wing is parallel to the gallery, closed off by a nine-foot-tall door. The 14-by-21-foot corner master suite has northern and eastern exposures, an en-suite Calacatta gold marble bath, and two walk-in closets. The 15-by-11-foot children’s bedroom has an en-suite bath and northern exposures, and a second children’s bedroom faces east and shares its bath with the library.

Wendy and Lee Chaikin — he is a managing director at the Cowen Group, a financial services firm — resigned themselves to finding a roomier home in the neighborhood after having their fourth child. Mrs. Chaikin’s wish list began and ended with the words “25-foot-wide townhouse,” an elusive and, if in immaculate shape, aggressively priced species.

“We loved this apartment at first sight for its great light, nice size, and a sense of prewar grandeur we were able to put our own stamp on with the renovations,” she said. “But we grew into it and now we feel, with the four kids, that we need more space. If we only had two or three, we probably wouldn’t have ever moved.”

The listing broker, Michele Kleier of Kleier Residential, found the Park Avenue co-op for the Chaikins eight years ago and, after an exhaustive two-year search, introduced them to the vintage Upper East Side carriage house — definitely spacious enough for a family of six, but in rustic, less-than-luxurious shape — that they are moving to. Unlike the full-service co-op they are leaving, the carriage house would never be described as turnkey, unless of course the incoming occupants were well-heeled equines.

Ms. Kleier expects the co-op will appeal to buyers who appreciate prewar details and a quiet location.

“With the great bones, the high ceilings, and the graciousness of the large rooms,” she said, “the apartment manages to combine Old World grandeur with all of the modern conveniences. The raised doorways add brightness and space and make it feel very grand, but at the same time, the renovation has given it a young and modern look.”