Her family's part-time housekeeper and close friend had been stabbed by the woman's estranged husband and left to die on the side steps of the Norman Street, Mangerton, home.

"My mother had only just ducked down to the shops and nobody else was at home," recalled the now 56-year-old Liz Pearce.

Her father, Ted Farthing, was a prominent Wollongong businessman at the time.

"Our family was profoundly traumatised . . . my parents could never talk about it and I was so frightened that I found it difficult to sleep in my own room for the next two years," said Mrs Pearce.

The family home was sold only two years ago, to a buyer who chose to demolish the house.

MORE: Flat's violent history no concern to owner

How much are real estate agents obliged to divulge about properties with dark pasts?

"Everything they know that could impact on a buyer's decision," says Illawarra Real Estate Institute chairman Charles Hegyi.

This includes not only serious crime but also other issues, from contamination to illegal extensions.

It is an issue that attracted attention in 2004 when an agency was fined $20,900 by the Office of Fair Trading for misleading behaviour over the North Ryde property in which Sef Gonzales murdered his parents and sister in 2001.

Buyers had lodged an $80,000 deposit on it but later pulled out after they learned (not from the agent) of the property's past.

Mrs Pearce said her family's agent, Colliers International, was instructed to make full disclosure about the killing in their house to any prospective buyer.

"Wollongong is a small community so we felt it was important for buyers to be aware of its history," she said.

Collier's Wollongong principal, Simon Kersten, said his agency was well aware of its obligations, citing the Property Stock and Business Agents Act regarding disclosure of material facts.

"It basically comes down to any material fact that would change a buyer's opinion of the property and it's up to agents to do their homework," Mr Kersten said.

He said one couple, once informed of the Norman Street history, lost interest but the eventual buyer did not have a problem.

Selling the house in Reserve Street, West Wollongong, in which former Wollongong mayor Frank Arkell was brutally murdered by Mark Van Krevel in 1998 was never an issue. It was demolished and redeveloped into villas.

But demolition isn't always an option; more often the house or unit that has been the scene of a crime must either be sold or retained by the family.

The Albion Park home of Jack Van Krevel (father of Mark Van Krevel), who was murdered inside his home in August 2000 by an associate of his daughter, Belinda, was sold the following year to a young couple.

"All we knew initially was that it was a deceased estate," said the husband, who did not want to be named.

"We had three children and my wife and I were looking for value and position and the house was perfect for us," he said.

"After the agent told us about the murder we sat down and considered it and still decided to go ahead.

"We had friends who said 'how could you live there' but we didn't have a problem with its past."

The current owner is aware of the history but chose not to speak to the media.

Some agents believe there are still some grey areas around selling homes with dark histories.

"How far back are you expected to go with this information?" asked Bevans agent Phil Murray.

"I sold Terry Williamson's [the Bulli rapist's] family home at Corrimal but by that stage the new owner didn't really mind, perhaps because he bought it as a knock-down," Mr Murray said.

It is generally believed the first sale after a dark incident calls for discounting, but there are no hard and fast rules on by how much.

"If the incident is really sinister then I'd say it's fair to discount by about 20 per cent," Mr Murray said.

Although gruesome murders are likely to have an impact on sale price, most agents spoken to believe this normally applies to the first one or two sales only.