What will become of late heiress’ real estate?

Clockwise: Huguette Clark, her Santa Barbara estate, her Connecticut home and 907 Fifth Avenue

It seems fitting that the late copper heiress Huguette Clark — a woman who lived her life behind a veil of secrecy and intrigue — has left behind a series of unanswered questions that are now gripping some of America’s most affluent communities following her death last month. Near the top of that list is the question about the 104-year old’s vast real estate holdings, namely, are any of her properties going to hit the market soon and who will be in the running to snatch one up?

The combined value of her real estate assets could be as high as a quarter of a billion dollars if estimates of her $100 million estate on the Pacific Coast in Santa Barbara, the $24 million country house in Connecticut and the $100 million co-op, the largest apartment on Fifth Avenue overlooking Central Park, at 907 Fifth Avenue, are accurate.

The Upper East Side estate includes one unit, which takes up all of the 8th floor and another that takes up half of the 12th. Combined, the duplex has 42 rooms. Clark lived at 907 Fifth Avenue, which is between 71st and 72nd streets, with her mother and then on her own for another two decades following her mother’s death in 1963, although she reportedly wasn’t seen there after being hospitalized 20 years ago.

Those two apartments would actually likely fetch “tens of millions of dollars,” said Tristan Harper, a senior vice president at Prudential Douglas Elliman and who is the listing agent on a $7.7 million two-bedroom property at 907 Fifth Avenue (3,300 square feet) and which sits above Clark’s 8th floor apartment. “It is very hard to say exactly because the condition is obviously an issue, but I was told that she had maids maintaining the apartment three days a week for decades,” he said.

But don’t go reaching for your pocketbook quite yet. Clark’s lawyer Wallace Bock and her accountant Irving Kamsler are reportedly under investigation by the Manhattan district attorney who is looking into the handling of her estimated $500 million copper mining fortune. Calls to Bock and Kamsler seeking comment were not returned. A spokesperson for the district attorney’s office declined to comment.

As it stands, only one of her marquee properties is currently up for sale for $24 million: the 12,766-square-foot mansion built on a 52-acre estate in New Canaan, Conn. The mansion has not been lived in for decades and has been on the market for several years.

“There has been some interest. It is a very intriguing house with a great deal of mystique,” said Barbara Cleary, president of Barbara Cleary’s Realty Guild, who along with Christie’s, is marketing the property.

According to Cleary, the mansion is in good shape and has been tended to by custodians over the years. She also said the property has been subdivided into 10 parcels, which would allow for 10 separate purchases or for an individual to acquire all of it at one time. “It could go to both types of buyers who have different interests. It isn’t focused towards any one type. This is a rare opportunity and it will be fascinating to see who does take advantage of it,” she said.

What seems certain is that Clark’s holdings have long been a subject of fascination for brokers on both coasts.

“I’ve been obsessed with this property for years,” said Michael Calcagno, a Santa Barbara-based broker for Sotheby’s International Realty who was referring to the 23-acre estate in Santa Barbara that Clark took control of in 1963 which is perched on a hillside overlooking the Pacific. It was in 1923 that Bellosguardo was sold to William Clark for $300,000. A decade later, the original the house was torn down to make way for the new home that still sits there today.

According to Calcagno, that property is known as Bellosguardo (“Beautiful View”), and would likely fetch somewhere between $80 million and $100 million, but he seems skeptical that there will be any movement before the all the outstanding legal issues surrounding the Clark estate are resolved.