Real Living managed and owned Pakuranga Park, Epsom Village, Remuera Gardens and Warkworth Oaks.
The company listed the Pakuranga property as being on more than 30 acres in the heart of east Auckland. That village had 191 independent living villas, 40 independent apartments, 28 serviced apartments and two community centres.
Remuera Gardens is at the end of a quiet residential cul-de-sac, Real Living says.
Epsom is advertised as having parks nearby and looking towards Waitematā Harbour.
The newest village at Warkworth was described as a place to enjoy a unique retirement community close to the Mahurangi River.
A source said the business was well-run with an established track record.
"Pakuranga Park is their big machine," he said. "They could potentially put up apartments at that site so it has potential."
Real Living's slogan is "retirement living villages exclusively NZ owned and operated for over 30 years".
Asked why the Murphy family might be considering selling at this point, the insider said Pakuranga Park was founded more than three decades ago and now could be the right time.
Certainly, interest in the sector is high with big returns from listed retirement village businesses and speculation that privately-owned Metlifecare is looking to buy BUPA.
"Like all families, they're probably saying where to from here? I can understand why they might be considering a sale," the insider said.
Real Living director Chris Murphy has previously expressed pride in the business being family-owned and offering a high level of service.
ING originally owned Remuera Gardens and Epsom Gardens before the global financial crisis.
ING sold those two villages to the Murphy family which already had the big Pakuranga property. The family then expanded by building the new Warkworth development, seeing potential for retirement village living in that area.
The Australian said Real Living was believed to be worth about NZ$400m "and is expected to attract some of the major Australian retirement living investors in its upcoming auction".
Forsyth Barr was reported to be working on the sale process and information memorandums have been sent out to buyers, the newspaper said. Forsyth Barr has not confirmed its involvement.
Real Living's annual return filed with the Companies Office last year showed Pakuranga Park alone generated an annual profit of $22m before tax. Equity in that one village was listed as being $176,043,000, the accounts showed.
Chris Murphy said Warkworth Oaks was the first retirement village built in that township. It had around 180 apartments as well as a rest home/hospital.
In 2007, the Herald reported on plans for a new retirement company set to float on the NZX. The company owned just two Auckland villages and even those close to the deal described it as a boutique offering.
ING Real Living announced then it would raise $100 million from the public and issue a prospectus, about the same time AMP Capital Investors sought $300 million by floating 80 per cent of its retirement business Summerset.
Some analysts and fund managers said the ING deal was too small to grab their interest and they questioned a related-party transaction proposed between the company and its new chief, the now-late Nick Wevers.
That deal never went ahead and Murphy family interests did the deal with ING to expand their business.