According to a neighbour the Pt Chev house had sat unoccupied for several weeks.
Professionals Real Estate salesperson Lawrence von Sturmer said the house was not advertised on the open market, rather, potential buyers were taken through on private viewings.
"We have a couple of thousand people on our database, so we picked the ones we thought were the best buyers for it."
The buyers were a "nice Kiwi family", von Sturmer said.
"As much of Pt Chev is. We do a lot of business in the area, we know the buyers really well and we can quite easily match up buyers with houses without doing that full marketing if that's what the owners are after."
He said for Ardern and Clarke, this had definitely been the case.
Von Sturmer said he did not believe the fact that the Prime Minister had lived in the home would have added to the sale price, which he declined to divulge.
He would not say whether the house had sold for above its CV - which was $1,120,000.
"The CVs are a complete joke - I don't even know what the CV is on that property," von Sturmer said.
Real Estate Institute chief executive Bindi Norwell said the median price for Pt Chevalier had increased by 16 per cent since the same period last year.
"For the three months ending February 2018, the CV for properties in Pt Chevalier was $1,400,000," she said.
"However the median sale price was $1,582,000 – 13 per cent above the CV."
Factors contributing to this included the area's proximity to the CBD, its access to the motorway, good schools and open space, Norwell said.
The property had sold on March 10, but the "sold" sign was only put up recently.
Nearby, a man staying at a home owned by his parents said he hadn't noticed any potential buyers being taken through the home in recent weeks or months.
Ardern and Gayford bought a new family home as they prepare for the arrival of their first child in June.
The larger property was valued at $1.7 million, according to online records.
The online listing, since removed, described the home as a bungalow haven. The 643m sq section features three double bedrooms, open-plan kitchen, a study, dining and family room and a master bedroom with en suite.
The yard has a large decking area and a sub-tropical garden, and even a tree house in a pohutakawa tree, according to the listing. The home is near Balmoral School (primary and intermediate) and is zoned for Mt Albert and Auckland Girls' Grammar schools.
Bayleys real estate agent Cheryl Crane declined to comment early last month and said the sellers weren't interested in commenting either.