The Irish have arrived in the Algarve, with a yearning for sunshine, the simple life, a few rounds of golf and the need to pour lorry-loads of punts into an obliging tax system.

No-one can put an accurate figure on it but an English restaurateur in the so-called Golden Triangle noted that up to three or four years ago his clientele was mainly German; now it's Irish.

In the Quinta do Lago golf club, at least 10 per cent of the membership is Irish. It is said that in one recent development in the area, some 70 per cent of the interest came from Ireland.

The reason no-one can ever put an accurate figure on the Irish invasion is that no-one can be sure about who owns what. This is partly because the Algarve is "a series of villages", as one estate agent put it, but also because the vast majority of properties are purchased through off-shore companies. The average investment is not in million-pound villas, according to another, but in the region of £100,000 to £130,000.

It's no coincidence that the great bulk of the Irish conveyancing there is carried out through a law firm called Braganca Bruno and Associados; it just happens to have an Irishman called Justin Ryan in its Almancil branch in the Golden Triangle. Discreet to a fault, Ryan will talk only about his golden rule: do what you would do at home.

In other words, get a reputable lawyer, reputable agent, reputable surveyor . . . It seems obvious, but for some reason, once abroad and in the market for a bijou home in the sunshine, many buyers seem to equate simple life and simple-mindedness.

At the click of a mouse, he will reveal all anyone needs to know about purchasing a property in Portugal, including the benefits of buying off-shore. These include avoidance of Portuguese purchase tax and advantages under Portuguese inheritance tax. The disadvantage is the annual cost of running an off-shore company, which can rise to £1,300.

Justin Ryan can be e-mailed at jrybbassoc.pt.