Tens of thousands of people are doing it every year. With some models . . .

Volvos, BMWs and Passats, for example . . . you can knock up to a quarter off the price of a similar model in Ireland.

With others, generally older cheaper cars, the savings are less substantial . . . 4% and 7% in two cases, quoted on a new website . . .www. importyourcar. net.

Other downsides are that you have to do a bit of paperwork, the trip across the Irish Sea costs a few hundred and you'll have to stump up thousands in Vehicle Registration Tax within 24 hours of driving off the ferry home.

There is also a reported reluctance among dealers to buy imports as trade ins.

This point evoked a wry smile when we put it to a spokesman for Car Giant, which has a huge showrooms at Wilsden, North London, handily located for Irish buyers a 15-minute taxi ride from Heathrow Airport.

"Irish dealers were the first ones to start buying cars from us. Now it's mainly individuals, but we still get a lot of trade buyers, " the spokesman says. He denies any suggestion that UK cars are inferior. "The fact that 1,200 Irish buyers buy cars from this outlet alone every year would suggest otherwise.

That's 200% up on previous years, " he notes.

In fact, he says, UK cars have higher spec and a much better tradition of keeping log-books up to date. Choice is also a big attraction for Irish buyers . . .

Car Giant literally has thousands of cars to choose from onsite.

"We have just been confirmed as the biggest car dealership in the world, so they have a lot to choose from. But they mainly come here for the price."

Strangely, he notes that most buyers are from outside of Dublin . . .

suggesting that country people may be cuter at driving a bargain, or at least are prepared to go more out of their way for one.

So how do you go about importing a car? One reader told us his story . . .

and warned of a particularly painful pitfall into which he inadvertently stumbled.

Sean* had his heart set on a snazzy new Lexus IS250.

However, the new price in Ireland would have set him back 58,000 . . . and he'd have to go on a waiting list.

And second-hand, they're not too common . . .

especially as he wanted an "automatic, with leather upholstery and premium pack" accessories.

"The closest I would have got was a blue one with leather but no premium pack for about 50,000, " he says.

Sean already had positive experience of importing from the UK. He'd bought a 4x4 and sold it on for the same price 18 months later . . . which meant he'd saved thousands in depreciation.

So how did he go about it.

"You can get a list of car superstores and garages on www. autotrader. co. uk. I waited until February because British reg plates change in March (and September) so dealers want to clear their forecourts for new models."

But wasn't he worried about buying a dodgy motor?

Of course, that's always a risk on both sides of the Irish Sea. In general, he says, UK cars do tend to be better looked-after . . . but watch out for salt damage underneath, which is a legacy of icy roads in the north of the country.

Sean points out that you can arrange an RAC (Royal Automobile Association) certificate.

This is an independent assessment that shows every fault down to scratches on the bodywork and interior blemishes. "It's a very detailed document and the dealer had it carried out and faxed it over, " he says.

Dealers can also provide what is known as HPI report, which shows if the car has any "form" on outstanding loan payments.

In Arthur Daley's day, you spat on your hand to seal a bargain. Our buyer did it the modern way and haggled by email. He bought a gleaming silver Lexus IS250 Executive with premium pack spec. It was just three months old and had 3,000 miles on the clock.

"The dealer met me at the airport, drove me to the showrooms and gave me the five-star treatment, and even a full tank of fuel for the drive home, " he says.

So far it had cost him 26,900 . . . plus 500 on flight, food, petrol, ferry.

He then drove to the Tallaght office of the Revenue Commissioners to hand over a further painful 13,100 in VRT.

Then the sting in the tale struck. Because the car was less than six months old, he was hit by a VAT bill for 5,500.

He warns prospective importers to be very wary of this particular pothole, which only applies to cars under six months old or those with exceptionally low mileage Still, even after stumping up for this painful VAT bill, he ended up paying a total of 46,000, when a lowerspec model would have cost around 50,000 in Ireland.

And horror of horrors, it would have to be blue . . . and not a gleaming silver, the colour he wanted.

A few months down the road, and it's still running like a dream.

"I'm delighted with the car. But I would have made a real killing but for the VAT, " he adds ruefully.