"Land use restrictions are now responsible for 56 per cent of the average Auckland house price, according to one of the Government's own reports.
"This cost is the single largest cause of poverty, inequality and sickness in Auckland and beyond."
Seymour said if two restricted zones were reclassified as residential a further 627,525 homes could be built (223,560 hones in the countryside living zone and 403,965 in the mixed rural zone).
"These are not treasured natural landscapes. They are grassy fields with the occasional barn or horse."
The Vitasovich family land is on the edge of the Waitakere Ranges Heritage Protection Area (WRHPA). In his book, Seymour criticises locals who see development of the land as "the thin edge of the whole mountain range being developed".
"They seem to have clout in the area. Labour's outspoken housing spokesman is from the West [Phil Twyford], and he won't say boo about the WRHPA. I ask a senior National MP who lives in the Ranges, who says, 'aww well, ahh, I live up there'."