A former Costco employee has opened up about how to spot the very best in-store bargains, urging shoppers to look out for telling coded clues on item labels.
Rachael, who used to work as a checkout operator at Costco, shared some in-store secrets on Channel 5's Costco: Is It Really Worth It, with viewers also learning how anybody can become a member.
The documentary looks at the inner workings of the membership-only retailer, with insight from shopping experts and others with inside knowledge.
Rachael went on to reveal the hidden clues that could see you reduce the price of your trolley items even further, urging shoppers to keep their eyes peeled for a 97p at the end of the price tag.
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As detailed in the show, this means the product has been discounted.
Rachael explained: "It could be reduced from the full price to that, so it could've been £20 and reduced to £9.97."
Also making an appearance on the show was retail expert and author Miya Knight, who has urged Costco members to watch out for asterixes on labels, which signify the product won't be coming back in stock.
Miya also divulged some of the clever tricks used by Costo to get customers to spend more than they'd originally intended to - telling customers not to be distracted by 'big wow' items at the front of the store.
She said: "They'll tend to put staples like milk and bread and the toilet paper right at the back....they put their big wow items right at the front to distract you.
"The layout is quite chaotic so often as a member you're having to go on a voyage of discovery every time. It's absolutely their aim for you to walk out with something you didn't intend to buy in the first place."
Rachael added: "The most common thing you used to hear was, 'I only came in for one thing.' You just used to laugh and then they'd spent over £100."
Advising customers to prepare before their Costco shop, consumer journalist Harry Wallop said: "The real trick with Costco is you have to go in with frankly a calculator and internet access and just check prices because it really does depend."
"Some things are fantastic value and some things aren't good value at all."
Costco membership is usually reserved for traders or businesses such as small grocery stores and takeaways, while those working, or in certain professions - including the NHS and public sector - also eligible.
Although you can shop online for as little as £15, only members can actually visit the warehouses themselves. Executive memberships are available for £74.40 for ordinary shoppers, with this including a 2 per cent cash back on many items.
However, Channel 5 revealed that anyone can get around the typical membership criteria, confirming with four Costco stores that those with either AA or RAC breakdown cover could become Costco members for the usual fee of £33.60.
They were also able to confirm that this was also the case for those with National Trust membership, as well as American Express credit card holders.
Do you have a shopping tip or inside hack to share? Email us at julia.banim@reachplc.com