I went to Costco the other day.

What an experience! Some much treasure, so little time to hunt. I can’t wait to go back next week.

The US-owned cash-and-carry chain continued its world domination plan when it opened a warehouse at Coomera on the northern end of the Gold Coast in June this year.

My wife Ali waited a while to allow the crowds to die down a bit before signing us up online, paying the $65 membership, and venturing out to the $75 million, 14,346 sqm shopping complex.

We are normally Coles, Woolies or Aldi shoppers. We frequent all three but are loyal to none.

Buying groceries, like everything else, has been getting more and more expensive each week and when you live on a fixed income you try to find ways to keep the costs down, especially now that we are in the midst of a much talked about cost-of-living crisis.

A bag of groceries 12 months ago cost us about $50.

Now that same bag is heading towards $80 or $90. On average our household of three adults spends about $350 a week on food and associated home cleaning products.

Friends who had already joined Costco instantly became evangelists raving about the low prices, the benefits of bulk packaging, and the randomness of some of the things that they find on sale. If you can’t picture what Costco is really like, then think about Aldi’s middle aisle, now multiply that by 50, and you are getting close.

We had a couple of hours to spare and thought we would put Costco’s “buy in bulk” mantra to the test and see if it delivers on its value proposition.

The car park was about three-quarters full when we arrived at 10:30am.

We waited almost 30 minutes to be issued with our photo membership cards which granted us access to the main shopping arena. While we waited I noticed a sign indicating that coffins were on sale this week, but only if you bought two. I have no idea what you would do with a couple of coffins once you’ve bought them home, but this was just the first of many surprises.

To be honest, nothing can prepare you for your first Costco experience.

The list of what you can buy is overwhelming, seemingly endless.

There were giant Samsung televisions and sound systems; coffee machines and mix masters; Callaway golf clubs and tennis racquets; giant slippery slides and theme park style inflatable pools; designer label clothes; clarinets, guitars and baby grand pianos; and everything you could possibly need for around the house.

Even though it was still early September, there was an aisle of huge American-style (but China-made) Christmas decorations.

There was a jewellery section with a diamond ring that retails for $99,000. “Who would buy a $99,000 ring from Costco?” I asked my wife. She didn’t have an answer.

If you are not careful, there’s every chance you could go to Costco to pick up some bread and milk and come out with an Apple iPhone 14 ($1969.99), a digital Air Fryer ($73.98) or an Intex PureSpa jet and bubble deluxe spa – a bargain at just $1,399.98.

The lighting is dull and the layout is chaotic. It really does feel like you are on a treasure hunt. Every time you turn a corner something new and shiny catches your eye. Oh, there’s a Panasonic NanoeX Air Purifier for just $349.99. I’ve always wanted one of them.

Everything has been super-sized. That’s partly how they keep the prices down and ultimately make their very healthy profits. That and the membership fee. The company made an astonishing $3.8 billion worldwide last year from collecting the membership fees alone.

Here are some examples of lower prices, but they do come with a catch.

We love the Danish butter, Lurpak. At Coles, it sells for $2 per 100 grams. The Costco price was $1.69 per 100 grams. To get that price though we had to buy two kilograms of butter. That’s a lot of butter. Coles sells it in 500-gram packs.

Coles sells Exit Mould for $1.90 per 100 ml. The Costco price is $1.53, but again you have to buy three 500 ml packs to get that price – which is probably a year’s supply.

Then there are the beans! Heinz Beans come in 555-gram tins at a cost of $13.99 for six. Coles sells the same thing at $3.50 per tin. Buying in bulk at Costco saved us $7.01 just on the beans.

I did however, when we came home, have to clear out a hallway cupboard to take the overflow from the kitchen pantry. I now have kitchen rolls and bottles of tonic water sitting next to my spare sheets and towels. Not ideal, but not the end of the world either.

So while we did definitely save money, how much did we end up spending in this one shop? $505.49. Yes $505.49. That’s much more than a normal shop, but the good news is we won’t be buying beans, butter or Exit Mould anytime soon.

Costco probably isn’t the place for single people to shop. But it is perfect for anyone who has a big family to feed or someone who is about to throw an end-of-year Christmas party.

Our three-person household plans to shop at Costco once a month and continue to top on fresh fruit and vegetables elsewhere.

It won’t take us long to get our $65 membership investment back in savings, especially as Costco also sells heavily discounted petrol – if you can stand waiting in the long queue and have the technological nouse to operate the pump.

Anyway, I’ll be heading back to Costco next week for a second shop and I’ve just noticed that there’s a Roland Drum kit on sale. The neighbours will be happy.