It's not the first time he's been charged with murder, and he had also been linked to two other murders over the past 30 years, but has never been convicted.

"In many ways they [the Durst family] are the kingpins of the private families," said Peter Slatin, a long-time New York real estate observer who runs the Slatin Group consulting firm.

The patriarch, Joseph, arrived as an immigrant from Poland in 1901. With savings from his job as a tailor, he bought his first commercial property, an office building on 34th Street, in 1915.

Joseph's son Seymour joined the firm in 1940 and, with help from his brothers, Roy and David, greatly expanded the family's office footprint in Manhattan's midtown, driving a series of landmark developments. Seymour's sons, Robert and Douglas, eventually joined the firm.

Douglas, who was promoted by his father over his troubled older brother, is considered a savvy operator. Unlike his outspoken father, though, Douglas, 70, eschews the limelight.

"He doesn't overblow his own horn," Slatin said. "He lets his family's activities in New York speak for themselves."

In the early 1990s, the privately held Durst Organisation made a key investment in a corner of Times Square and landed a key tenant, publisher Conde Nast, that brought cache to a troubled redevelopment area that had not been considered a prime market for office tenants.

Today, 4 Times Square is an anchor for the area's resurgence and part of the Durst company's office portfolio of 13 million sq ft.

A short distance to the east on 42nd Street is One Bryant Park, a Durst building that is the New York headquarters for Bank of America Corp. The real estate firm also owns key properties nearby.

Durst Organisation also owns 1,250 high-end apartments and is developing 1,100 more units, all in Manhattan. A few years ago, the firm bought the debt of a building in a then-unglamorous area of midtown known as Koreatown.

It is now set to open a mixed-use development with 375 apartments, where two-bedroom units will be priced at about US$8,500 a month, said Jordan Barowitz, a company spokesman.

The family is entrenched in the company, which is said to be worth more than US$4 billion, according to the 2014 Forbes list.

Douglas runs it with his cousin, Jody. Two of Douglas' children, Alexander and Helena, work as vice-presidents, along with other members of the extended Durst family.

Soft-spoken and courtly, Douglas Durst takes a special interest in environmental projects and owns one of the largest organic farms in New York state.

On a tour of One Bryant Park given to a journalist shortly before it opened a decade ago, Durst pointed with pride to the building's many energy conservation features.

The building was the first high-rise office tower given 'platinum' status for environmentalism by the US Green Building Council.

Like other top New York real estate families - the Rudins, the Roses, the Resnicks among them - the Dursts are deeply involved in the city's philanthropic and social scene. Douglas Durst, a graduate of the University of California at Berkeley, is a patron of the theatre and sits on the board of two theatre companies as well as the New School. He also is a director of the Real Estate Board of New York, one of the most powerful and influential players in New York City's government.

What separates the Durst family from its private real estate peers is that it has not strayed from the New York market and remains overwhelmingly concentrated in midtown, the most expensive office market in the US.

In 2010, however, it ventured downtown and won the right to invest US$100 million in One World Trade Centre, the long-delayed and troubled project to replace the twin towers destroyed in the 2001 terror attacks.

In winning the bid, Durst became a co-investor with the Port Authority of New York and New Jersey, the bi-state agency that built the giant office complex in the 1960s and struggled to redevelop the area.

Durst has taken over responsibility for construction, leasing and management of the 541-metre tower.

Downtown has long been considered a second-tier market in the city, but Durst was instrumental in bringing a prime tenant to the trade centre project - Conde Nast. The publishing firm's quarters at Times Square will be leased to new tenants.

For now though, the family's real estate achievements are not making headlines as the nation awaits the next chapter in the Durst murder case.

In law enforcement's sights for decades, eccentric Durst prompted investigations across the country - from Houston, where three of Durst's condominiums were searched last week, to northern California, where the disappearances of two teens in 1997 raised questions about his location at the time.

The 71-year-old was arrested in New Orleans last Saturday with a handgun, marijuana, a fake ID and over US$42,000 in cash, one day before the airing of the final instalment of an HBO documentary, .

In it, he was presented with evidence of similar handwriting on two envelopes, one from Durst and another probably from Berman's killer, and was later picked up by a microphone saying he "killed them all".

On Wednesday, he was said to be suicidal, according statements by Louisiana authorities, after they moved him to a facility for inmates suffering from acute mental illness.

Berman was shot in the back of her head at her home in Beverly Hills, a day before she was due to be questioned by police who had reopened an investigation into the 1982 disappearance of the tycoon's wife, Kathie Durst, in New York. Durst had long been under suspicion over his wife's death in 1982, but has denied any involvement.

He was also charged in 2003 with the murder and dismemberment of his 71-year-old neighbour in Texas two years earlier, but was found not guilty after a trial in which he claimed self- defence.

The trial was a spectacle in which his attorneys argued that after the killing, a previously undiagnosed mental condition propelled Durst into a traumatised state similar to an out-of-body experience.