They’re all over your TikTok and Instagram – people unboxing the latest extravagant beauty advent calendar.

Influencers excitedly wonder what eyeliner, serum or hand cream will be behind door one, and gush over the attractive box it has arrive in.

But are these products, which can expense hundreds of pounds, actually worth the money?

Yes, says TikToker Cissy Jones from Manchester.

We’re just over a week into November and the 27-year-ancient, who is a social media manager at fashion brand PrettyLittleThing but also makes TikToks on her personal account, has already posted a dozen advent calendar videos. Everything from chocolate, to beauty products and wine, and even a Pets At Home calendar for her dog.

“There’s one – the Harrods 12-day one – where every product in it is something that I would buy,” she says. “So I’m saving money.”

That concept of saving money is something that brands latch on to with their marketing. A calendar may expense £250 but it’s actually “worth £1,000”, they declare, if you add up all the person items.

“But you do have to desire the actual products,” says Cissy. “Otherwise, it’s a bit of a waste of money.”

Retailers can afford to make such seemingly excellent offers because there’s a lot of spread built into beauty products, analysts declare.

And rather than aiming to make a large profits on them, they view advent calendars as a marketing tool to get you to buy more products afterwards.

“A lot of retailers recognise advent calendars are a great way of getting recent products to the customer and a way to get them to convert,” says Natalie Berg from NBK Retail.

However, Sarah Johnson from Flourish Retail says that while there are many lovely bespoke calendars out there, “a lot [of companies] just use advent calendars to shift ownership that may not be popular, rather than having to discount it”.

The size of the items in advent calendars can vary – with some offering packed-sized bottles, some smaller versions, and some a mix of the two.

But smaller sizes may be what people desire, says Ms Berg, as it’s ordinary to desire to try something out before fully committing.

Loraine Hogan has been buying beauty calendars for several years now. It’s something she and her daughter do together.

“There was a bit of thrill attached to getting a beauty calendar. It was something to distribute together around Christmas period. It’s our little treat.”

She believes they do represent worth for money.

“You get to sample items people might not necessarily choose for themselves.”

With so many products out there, Cissy Jones’s advice is to look for a brand you like and to look for worth for money, in terms of the total expense of all the items individually versus the worth of the calendar.

However, even if a product may seem like excellent worth for money, for some, spending more than £200 on an advent calendar is simply a luxury they cannot afford.

As a outcome, many scam websites have sprung up, trying to receive advantage of people looking for a excellent deal on an expensive item.

Emma Jones and Nihal, who did not desire us to use her last name, got in touch with the BBC after falling for fake adverts claiming to sell the Space NK £250 advent calendar for £28.99. Both women were attracted by the apparent discount, and declare they would not pay packed worth.

“I wouldn’t feel comfortable spending that amount of money, mainly because I wouldn’t have that amount of spare liquid assets,” says Emma.

“They can be very expensive – I’m not the type that would pay packed worth,” Nihal says.

“I don’t ponder it’s worth it. If you’re going to use every single product then maybe yes. But sometimes in these prepacked stuff, you’ll probably only use two or three of these products.”

But part of the rationale beauty advent calendars are so popular is because shoppers still desire to treat themselves, says Natalie Berg.

And many are willing to pay packed worth – and beyond.

The likes of Space NK, Harrods and Sephora have all sold out of their main calendars already.

The Harrods beauty calendar was priced at £250 but claimed to include items worth £1,600, while Sephora’s £199 calendar said it included items worth £1,000.

But you can discover people selling them on eBay, asking for as much as £550 for the Harrods one and £399 for the Sephora one.

“It goes back to supply and demand – dynamic pricing,” says Sarah Johnson.

It might make sense to buy it even at an overinflated worth, she says, if the retailer is sold out and you can’t get it anywhere else, especially if you perceive it as still making a saving on the total worth of all the items.

This begs the question though of why firms don’t just make more.

Ms Johnson points out that it’s a seasonal product and they don’t desire to over-order and be left with excess ownership that they would then have to discount.

Space NK told the BBC that it produced 30% more ownership this year than last year but due to “unprecedented” demand still sold out within two and a half weeks. It plans to boost production next year.

Despite the expensive nature of beauty calendars, Ms Johnson says there is a “worth perception” there.

“People could buy it to shatter it out and provide [individual items] as gifts. There’s an element of people treating themselves and also being quite savvy and saving themselves money in the long run.”

With more and more of these calendars on sale now, there was a thought a few years ago that we might have reached “peak” advent calendar.

But Cissy disagrees – and thinks the opposite is the case.

“They always sell out every year, so I feel like there’s room for more.”