The idea for Dublin Antique Tours came when Keith Murphy and some friends sat down to a dinner party together a few months ago. "There was all this talk about dotcom businesses at the time and we were talking about what we thought would be good ideas, so we all wrote down an idea on pieces of paper and put them into a bowl. Mine came out, so we decided to give it a try," says Murphy.

The idea was for Dublin Antique Tours, of which he is now the director. A car and guide will pick you up at a hotel location or, if you live fairly centrally in the city, at your house. Then it's off antique hunting.

The day usually starts in Francis Street, which has long been home to several antique shops. Then it's on to Powerscourt Townhouse Centre, and some shops in the surrounding streets, such as Molesworth, Drury and South Anne. Parnell Street, Capel Street and Clanbrassil Street are also covered. There are a number of other places the tour will also visit, depending on what items people are looking for.

Apart from the tour of the shops, there is also an option of a day going round auction houses or antique fairs, both in Dublin and locations further afield such as Kilkenny. And if you can't find the time to go on a tour yourself, you can pay the company to search for the pieces you want.

Murphy's background is in the antiques business in England, where he specialised in fine art. He returned to Ireland six months ago, and the tours have been running for almost three months now.

"It seemed like there was a gap in the market for this service," he says, as we begin the trek down Francis Street. "I thought it would mainly be tourists, but quite a lot of Irish people have been coming along too."

The groups are kept small, usually between two and four people, so that everyone gets advice and attention. Carole De Lavari and her family have recently moved back to Dublin from London, and she is looking for some furniture for their period house. "I'm looking for a dresser, either oak or pine, for the kitchen. And I'm also keeping an eye out for a chest of drawers for my own bedroom."

At O'Sullivan Antiques, there are some really jaw-dropping pieces - and prices. An enormous 18th-century roccoco-style mirror has a price tag of £45,000. "That's too fussy for my taste," De Lavari says. "But my husband would love it." Also in the same shop is a brass and stained-glass lantern for £8,000; a Victorian walnut davenport for £2,500; and a brass inkwell you could put on top of it, should you so fancy, for £650.

Murphy, who operates solo from the dealers and does not, for instance, get commission from a shop should someone choose to buy there, acts as a kind of antiques policeman. In a shop further down the street, De Lavari sees a chest of drawers that she likes. Murphy asks the owner to pull the drawers out. They look fine to an untrained eye. Afterwards, he points out that the body of the drawer was not original: the front part had been grafted onto modern wood with machine-work.

"I would never have thought of looking at a drawer like that," De Lavari says, astonished.

After that, we do a lot of pulling out of drawers, and like anything, once you know what to look for, we start recognising when the piece is not original. This is also an opportunity to learn about wood. Although most of the furniture is various shades of mahogany, by the end of a morning, I'm finally acquainted with walnut, rosewood and satinwood.

There are not many original Irish antiques left in this country now: much was sold in the first half of the 20th century, with the breaking up of the big houses. Dealers import items and sell them on, and they are not cheap.

"I'm surprised to see how expensive things are here compared to the same kind of things in London," De Lavari comments.

"It's all about supply and demand," Murphy concedes. "There are a huge number of people buying now, and there isn't enough stuff to keep up with the demand." Hence, presumably, the huge price-tags that dangle insouciantly off everything we see. It's not only period houses that command big prices these days, but also their potential contents.

An antiques tour costs £100 per person. More information from 01-2865247, or by visiting www.dublinantiquetours.com