"It was the place Fred used for planning his strategies. He was a hands-on coach.
"Fred had the wonderful ability to be able to mould them together - to mould a group of men into one unit so when they went on to the field they were completely compatible."
The class of 67 included Sir Brian Lochore, Chris Laidlaw, Sid Going, Kel Tremain, Colin Meads, Earle Kirton, Fergie McCormick, Ian Kirkpatrick and Waka Nathan.
Keen to build team morale before the journey to the Northern Hemisphere, Sir Fred gathered them in Whangaparaoa for several days before the departure date.
Some of the senior players bunked down in the rumpus room on mattresses and stretcher beds. Others were billeted with Sir Fred's friends in the area.
During the day they were able to train on Manly Beach, across the reserve at the bottom of the section, away from prying eyes.
In later years, the house remained a gathering place for rugby greats, said Mr Sayers.
"Every tour that came out here, every rugby tour would say, 'while we're here we've got to go and see Fred Allen'."
Sir Fred is widely regarded as an All Black great for his legacy as a player as well as a coach.
He played 21 games, including six tests, between 1946 and 1949, all as captain.
His coaching career began with Auckland at a time when the side successfully defended the Ranfurly Shield on 25 occasions.
He became All Blacks coach in 1966, winning all 14 tests, and remains the only All Blacks coach never to have lost a test.
Sir Fred was the holder of an OBE, and was knighted in 2010.
He celebrated his 90th birthday at home two years ago with past All Blacks including Sir Wilson Whineray, Sir Brian and Bob Scott - now the only surviving member of the 1946 All Black side.
Sir Fred bought the Whangaparaoa property in the 1950s, first using two army huts at the bottom of the 1055sq m section as a holiday home.
The present house was built in 1967 to make the most of the expansive views overlooking the outer reaches of the Hauraki Gulf.
Sir Fred's nephew, Alex Carpenter, said he had lots of memories of the home, particularly from the last years of his uncle's life.
Putting the property on the market was sad but it was what his uncle had wanted, said Mr Carpenter, who hoped it would go to a rugby fan.
"It would be nice if that was the case, if it went to someone with a love of the game," he said.