Protests took place at the open home day for TV show The Block.
About 30 people marched down St Johns Road to draw attention to the Auckland housing crisis and homelessness.
"We just think it's a really strange situation where you have this housing crisis, and at the same time there is this primetime TV show that is all about basically property speculation - getting a house and doing it up and flicking it off and the winner is the one who makes the most money," said Unite Union organiser Ben Peterson.
"Money and resources can be found to build a house in a short amount of time for the purpose of getting ratings, but not to build state houses and not to fix up the damp houses that we have," he added.
Mr Peterson said a first home buyer would need a 20 percent deposit of $228,858 to buy one of the houses, and based on Kiwibank's mortgage calculator, would then have to pay $1085 a week on a mortgage - impossible sums for the average family.
"All those thousands of people who will come and look at the house at the weekend but no one will actually have a chance to buy it," he said. "The people who will buy it will be investors or from the upper end of town."
A spokeswoman for Mediaworks, which screens the show on TV3, said the company had no comment to make.
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