Police are searching for the killer of one of the city’s most successful real estate agents, Linda Stein, who was found late Tuesday night bludgeoned to death inside her apartment at 965 Fifth Ave.

Stein, who helped rock stars and movie moguls buy and sell their Manhattan apartments, was beaten to death inside her 18th-floor apartment with what police sources described as a heavy, blunt object. Her body was discovered face-down in the living room of the apartment at about 10 p.m. by her daughter, Mandy Stein, police said.

Linda Stein had sustained serious blows to both her head and neck, a spokeswoman for the city’s medical examiner, Ellen Borakove, said. A weapon was not found at the scene, nor had police identified a suspect.

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Investigators spent yesterday attempting to track Stein’s last steps, police said. She was last seen Tuesday morning by her daughter, one police official said.

“We don’t really know what happened,” Mandy Stein said. “People are tirelessly working to find out.”

Faith Hope Consolo, who worked with Stein at Prudential Douglas Elliman, said the two spoke on Tuesday. Stein told her that she was planning to meet that evening with a couple that the two shared as clients. Ms. Consolo declined to identify the clients.

“Today is the first day I haven’t spoken with her in a long time,” Ms. Consolo said.

While police yesterday did not publicly state that an assailant would have required access to the apartment in order to kill Stein, friends said it would have been difficult for someone to break in. The building, which is on the corner of East 78th Street, has at least two doormen patrolling the lobby at all times, and Stein’s apartment had a private elevator operated by a building employee, Ms. Consolo said.

A friend of rock stars Elton John and Paul McCartney, Stein had brokered residences in New York, the Hamptons, and Europe for celebrities such as Madonna, Sting, and Steven Spielberg.

Friends, who described Stein as an energetic leader and philanthropist, were in shock over the killing.

“I can’t imagine who would have done this,” a friend, Evelyn Lauder, who is the senior corporate vice president of the Estee Lauder Companies Inc., said holding back tears. “She had a wonderful relationship with her family and her ex-husband.” For the past 10 years Stein served on the board of The Breast Cancer Research Foundation, which was founded by Mrs. Lauder in 1993.

A survivor of two bouts with breast cancer, Stein, 62, was athletic and in fine health before her murder, friends and family said.

“This weekend I hiked with her for an hour and twenty minutes,” daughter Mandy Stein said. “I’m running the marathon on Saturday and she kicked my butt.”

The daughter of Ira Adler, a kosher caterer in the Bronx, Stein graduated from Teachers College at Columbia University and became a fifth grade teacher in Riverdale.

Soon after, she married a record mogul, Seymour Stein, and began a career in the rock and roll business, managing bands such as The Ramones and the Deal. The couple divorced, yet remained best friends, a spokesman for Mr. Stein, Liz Rosenberg, said in an e-mailed statement.

After years in the music industry and a prolonged stay in Paris, Stein moved back to New York and entered the real estate business.
“Doesn’t everyone think there is money to be made in real estate?” Stein told The New York Sun during a 2005 interview when asked why she traded guitars for penthouses.

Madonna, who launched her music career at Sire Records with Seymour Stein, was Linda Stein’s first high-profile real estate client.

“She didn’t want to spend more than a million dollars,” Stein told the Sun in the 2005 interview. “So I found her an attractive apartment on Central Park West.”

Stein had another daughter, Samantha Lee Wells, who worked with her at Prudential Douglas Elliman. She is also survived by her father, Mr. Adler, and her sister, Arleen Adler.

In 2005 Stein told the Sun that she sold between 20 or 30 properties a year, with her smallest deal in the previous year being worth $2.5 million and the largest netting $30 million.