None of the neighbours spoken to by APNZ, some of them long-term residents, were aware Ms Furlong had lived there.
Investigation head Detective Inspector Mark Benefield said police were acting on information they had recently received but would not reveal where it had come from.
"It's just information that's come to the inquiry."
Mr Benefield would not say whether anything related to the case had been found in the search.
Ms Furlong had lived in the flat with her boyfriend Danny Norsworthy, the father of her son Aidan who was just 5 months old when she disappeared.
A funeral service was held earlier this month to finally farewell Ms Furlong, 19 years after her disappearance.
CAN YOU HELP?
If you have information on Jane Furlong's death contact police on 0800 675 263, email furlong@police.govt.nz or visit the special "What happened to Jane" Facebook page. Alternatively call Crimestoppers anonymously on 0800 555 111.