This is despite the fact Labour has ruled this out a number of times – Labour leader Jacinda Ardern called Collins' comments "mischievous and wrong".
Speaking to reporters in Wellington today, Ardern said: "I consider that the last roll of the misinformation dice".
But this did not deter Collins who doubled down on her claims.
She said it in a party press release; she said it in an email to supporters; she said it over a bullhorn at a busy intersection and she said it again when talking to media.
"Do you want a wealth tax?" she asked over a loudspeaker to supporters – "no!" yelled a chorus of volunteers wearing blue windbreakers, all holding signs.
"What does a wealth tax mean?" she yelled. After a confusing couple of seconds with no reply, Collins finished the chant herself: "Labour/ Greens!"
She had fuelled up on oysters bought at a farmers' market in the North Shore, before meeting her supporters in New Lynn.
It was mostly handshakes and hellos at the market, but before she left, she bought a mug featuring her caricature next to the caption: "My husband is Samoan so, talofa" – a reference to a line in the first leaders' debate.
"That's excellent," Collins said after a long laugh. "I love that, that's a good piece of humour."
Speaking to media later in the day, she said she was having "a lot of fun".
"Campaigning as the leader is one of the most exhilarating things I've ever done."
She started her media stand-up by introducing reporters to one of her second cousins who was with National supporters waving signs at passing cars.
The pair had just met for the first time – "our grandmothers were sisters; there were seven daughters and seven sons in that family."
Her family, she said, was "pretty much everywhere".
Collins' second cousin watched on with 30 or 40 sign-waving National supporters as she hammered home her wealth tax point.
She was also quizzed on why National's Te Atatū candidate, and MP, Alfred Ngaro was not at the event.
Just days ago, she was forced to defend what Labour's Phil Twyford called "gross information" regarding one of Ngaro's Facebook post about Twyford's views on abortion.
Collins said Ngaro was out campaigning in his own electorate.
She was also asked why her campaign diary had changed and she would now no longer be going to the Tauranga and Bay of Plenty this week.
These electorates are the home of recent former leaders Simon Bridges and Todd Muller.
These are "already strong National seats," she said, adding that her focus would be on Hamilton, where she is heading instead.
Collins finished her day on the trail by watching the All Blacks play Australia with supporters at an event centre in Karaka.
Despite the game was being played on the other side of the country, Collins made sure those at the game had National front of mind as they watched the clash.
"Go the All Blacks," a National Party ad by the stadium said.
