I’m off with some girlfriends on a shopping trip to New York. Great now that the pound is so strong, but someone has told me there’s a limit to the value of purchases that we can bring back into the UK. Do you have any advice? Imogene Tate, London

A Sunday Times travel expert responds: It’s true that with the dollar being weak, the temptation is to shop while it’s dropped. But before you start clearing the rails at Bergdorf Goodman, Banana Republic and Barney’s, you should remember this isn’t quite the free-for-all bonanza it seems. Just ask Mrs Rooney, who was famously stopped by customs for blowing her allowance (and how) on a ex-EU shopping spree. In fact, you are only allowed to bring back £145 of ‘other goods’ (i.e. anything not booze or cigarettes) without paying duty which can, of course, wipe out any savings.

True those savings can be considerable. An iPOD 30GB with video playback costs around £175 here; they are £125 or less in the US, if you shop around. Similarly, the 4GB Nano is £135/£100. But be careful as you move up the price chain. It’s OK getting a pair of Levi's 501s for £25 as opposed to £40, but although Tag Huer Formula One watch may be only £223 in the US compared to £320 here, that’s blown the allowance and some.

There is another sneaky bubble-bursting bugbear, too. It’s called sales tax and it adds a variable amount on for each state. Some (Alaska and Delaware, for example) have zero sales tax, California is 7.25 per cent, but it can range up to more than 9 per cent in parts of New York State (counties can add there own little percentage); it averages around 5 per cent across the US. It is usually added on at the till, which can screw up your calculations.

So, I know you wouldn’t, but what if you decide to try and get more than your allowance through? Well there are the usual ploys - cutting out labels and/or wearing the clothes in the US before coming home (make sure all receipts and bags are dumped) so they don't look spanking new. I had a friend who went out to buy the same laptop as his mate and took said friend’s receipt with him, so he could prove it was bought in the UK. Devious, eh? By the way, the Excise people are trained to spot new (and genuine) Rolex watches and expensive engagement rings bought at Tiffany.

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