Can you bag a bargain at duty-free or will impulse buys waste your cash? Maria McCarthy looks at why it's hard to fight the temptation to splurge at the airport.
At the airport waiting for my departing flight I'm bored and stroll round the duty-free shop.
I try on some sunglasses and decide they really suit me. There's something about airports that always makes me feel more glamorous.
Then I spot the high-end cosmetics counters.
Save or splurge?
A friend of mine who flies a lot for work says she always gets her make-up and beauty products at the duty-free shop as you don't pay 20 per cent VAT on them, making them better value.
However, other friends have told me you can get better deals online, or even on the high street if you watch out for special offers.
I resist the sunglasses and cosmetics but I do splash out on a trashy paperback novel - despite knowing I could get that cheaper online.
When it comes to shopping temptations, the return flight is even worse.
I'm at Charles de Gaulle airport in Paris on my way back from a work trip and find myself very taken by various attractive gift sets of chocolate and wine.
Then rather bizarrely I find myself with a strong impulse to buy a large pink glittery model of the Eiffel Tower.
Now, I like buying souvenirs of trips, but I'd already got a fridge magnet and that was plenty! Also, doing the conversion from Euros to pounds, the model was about £20.
Thankfully, I managed to resist the urge - which is just as well as I can't imagine where I'd have put it when I got home.
But I was curious about why I should feel so compelled to do something quite out of character.
Psychologist Benjamin Fry, who co-hosted the BBC3 show Spendaholics believes it has its roots in emotional insecurities caused by the airport environment.
Shopping = security
"As humans, we can find unfamiliar experiences such as being in an airport and travelling by plane unsettling.
"In response we look for ways to feel more secure – maybe by buying an expensive watch or make-up so we feel more attractive and powerful.
"This isn't logical of course, because if you did run into a problem of some sort when travelling you'd probably be able to deal with it much better with extra money in your bank account than if you had less cash available because you'd splashed out on luxuries."
And although carting around a tacky model of the Eiffel Tower isn't exactly going to make me look attractive or powerful, Benjamin believes the principle is the same in the sense that it takes me back to a time of emotional security.
"The object is like a toy, and it probably reminded you of when you were a little girl and your parents might treat you to something pink and sparkly."
Of course other factors in airport shopping can be boredom and that sense of wanting to get into the holiday spirit by treating yourself.
And then, of course, there is the belief that you will get a bargain when shopping tax-free and duty-free airports.
However, the rules on tax and duty can be complex and influenced by different factors such as whether you are travelling within our outside the EU.
Also, some shops charge an expensive initial price so the duty-free saving is offset. As with so many things, the best strategy is to plan ahead.
What to buy at the airport
If you are planning to buy cosmetics, electrical goods, cigarettes, alcohol or other goods at the airport, check out their website first, most of which have contact details for the various concessions.
Then call up and check the price of what you'd like to buy.
I did this with a bottle of my favourite scent, Chanel No. 5 (100ml Eau de Toilette) which would cost £76 at Boots online, but £63.33 at the Chanel shop in Heathrow.
So there are bargains to be had but do your research before you set off, be aware what you are and aren't allowed to carry in your hand luggage.
And avoid pink glittery Eiffel Towers unless your decorating style is unapologetically kitsch!