Susan M. Cobaugh, a businesswoman who moved to Georgetown last year, had grown increasingly frustrated in the months before the murder of a former business partner.

An acquaintance of the two said Cobaugh would travel -- sometimes twice a month -- to the home of the former business partner, Daniel C. Herbert, after he failed to return money she had paid him to secure a loan for her company.

R. Larry Edinger, who said that he was swindled out of $14,000 by Herbert in 1997, said Cobaugh, who went by the nickname "Bobbi," would often call him and complain about Herbert not repaying her. Edinger said she became "obsessed" in 2002, when she made monthly trips from New Jersey, where she lived at the time, to Upstate New York to confront Herbert about the longstanding debt.

Edinger said Cobaugh would call him and say, "I'm on my way up to irritate" him, a move Edinger said showed how her impatience with Herbert turned to rage.

"She'd stand on the lawn and yell at him, 'Give me my money.' It came to the point that she was obsessed with him."

Late last month, Cobaugh, 38, tearfully pleaded guilty in an Onondaga County, N.Y., court to her role in Herbert's slaying in December 2002. Under a plea bargain in which she can be sentenced to 20 years to life in prison, Cobaugh admitted to hiring a hit man.

She entered the plea after prosecutors were handed secretly taped conversations between Cobaugh and her accomplice, John Gradia, said Chief Assistant District Attorney Michael Spano.

In one of three conversations taped by Gradia, a New Jersey building contractor, Cobaugh can be heard asking him if he had cleaned the steering wheel of the car thoroughly because he had blood on his hands when they left the crime scene, according to Gradia's attorney, George Hildebrandt. Hildebrandt obtained the tapes from an unidentified acquaintance of Gradia and handed them over to the prosecution.

Spano declined to comment on the contents of the tape.

"I will say that they contain inculpatory statements by her, but the specifics, I can't go into at this point," Spano said.

Prosecutors allege that Cobaugh paid Gradia $20,000 to murder Herbert, to whom Cobaugh had paid $250,000 in 1998 to acquire a $5 million loan for Advanced Healthcare Inc., a company she headed. Cobaugh never got the loan. According to court documents, her company stood to collect $2.5 million from a life insurance policy on Herbert, in the event of his death.

The prosecution was prepared to argue that Cobaugh was present at the home of Herbert when he was shot, stabbed and beaten in December 2002. She and Gradia had planned the crime for more than a year, the prosecution said.

During another taped conversation, Gradia said while he was at church he felt guilty for the crime, Hildebrandt said. Cobaugh responded by saying, "I don't feel bad at all," Hildebrandt said.

In other conversations, she expressed trepidation about the police investigation and annoyance at not being able to obtain Herbert's death certificate, Hildebrandt said.

Defense attorney Thomas W. Ryan conceded that the tapes were damaging to his case, but he declined to comment on his client's demeanor as she heard them being played. "Certainly it would have made things more difficult for us," Ryan said.

According to Ryan, Cobaugh, a New Jersey native, moved to Washington in August 2003, settling in Georgetown to pursue business interests. A single mother, she enrolled her teenage daughter in a Virginia school she still attends while living with an aunt.

Patrick G. Merkle, who was Cobaugh's landlord for a month while she lived in the 3000 block of N Street NW, said that she did marketing for a Chicago-based company.

"Bottom line, you have a woman who was squeezed very, very hard financially," said Merkle, a Washington attorney who served as a consultant on the case.

Edinger was prepared to testify at Cobaugh's trial, which was set to begin Monday. "She was ruthless. She was one hell of a businesswoman," he said.