Big hype this week about Costco, the world’s largest retailer after Walmart, opening one petrol station in Auckland’s northwest.

The retailer is expected to open its big warehouse later this year, including groceries, a tyre centre, a pharmacy, a food court, and an optical and hearing aid centre

So the big question is will Costco bring the gull effect to the supermarket duopoly?

Costco managing director Patrick Noone joined Heather du Plessis-Allan.

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