Riverton resident Marina Seager said she had even composed a handwritten letter with glitter to Costco bosses in 2018 to be its first New Zealand member.
She was rewarded with an invitation to the store's VIP opening last night.
Speaking to the Herald from inside the store this morning soon after opening to the public, Seager said she was "absolutely stoked" and had a "full trolley" already, parting with around $800.
"I live in a 30-bedroom house, so I need to buy in bulk and Costco gives you good deals and is also cheap.
"I am actually distressed I can't put more things in my trolley.
"I flew here last night so I might have to get someone to pick me up with all the stuff."
Seager opened her big family home of 13 years to whānau in need.
She said it was haven for people to stay when they had nowhere to go.
"We have had foster children, and people who need a home-stay here.
"I was able to buy some really nice pillows for them at Costco today."
Seager rented a room in Massey for the night, and took an Uber to be dropped off at the new mega store.
"I arrived there at 7am, Costco opened their gates a few minutes after.
"Because I was invited to the VIP opening night it was easy for me to know where to go to get specific things.
"I was in and out within an hour.
"It was packed. Many people were posing with Christmas trees, other items, taking pictures."
"I was expecting it to be more, I bought a full trolley and then some. I bought things which my family sent me to buy for them, my brother wanted the Kirkland golf balls, I was able to get that for him."
However, Seager doesn't plan to take daily flights to Costco.
"But I will be here every time we are in Auckland. I am here today especially because I waited for three years. It's a celebration."
The Washington State-headquartered retailer sells US$192 billion of goods annually.
Costco Wholesale, founded in 1983, has four New South Wales stores, four in Victoria, one in Perth, two in Queensland, one in Adelaide and one in Canberra.
It has stores in the United States, Puerto Rico, Canada, United Kingdom, Mexico, Japan, Korea, Australia, Spain, France, Iceland, China and via a majority-owned subsidiary in Taiwan.
The Auckland warehouse is a $100 million-plus membership store, costing $60/person or $55/business annually.
It buys most of its merchandise directly from manufacturers and its strategy is to provide members with a broad range of quality goods at prices consistently lower than elsewhere.
