The £1 million-plus homes sold to young couples in Carrickmines will undoubtedly mean large mortgages for many. In just four hours on Thursday of last week, 15 of the homes - each costing around £1 million - were sold.
And they were sold to couples in their 30s and not to rock stars or other celebrities who traditionally make up much of the market for trophy homes.
The buyers were a mixture of professionals: executives in the computer industry, a stockbroker and some business people. One was even a first-time buyer.
While the runaway prices at the top end of the market have far outstripped most people's salaries, they are still affordable for a few.
Those moving into the Carrickmines development are mostly trading up from smaller houses in the surrounding area and these will fetch substantial prices. Even so, the balance and the remaining mortgage may mean loans as high as £750,000 for some people. Most of their former homes are in the £500,000 to £750,000 bracket.
Others of course, have inherited property and have substantial investment income from other properties, which will go some way to offsetting the cost. Nevertheless, some of these couples could be facing monthly repayments as high as £3,135 for a £500,000 loan or £4,702 for a £750,000 loan.
Banking sources say the big change over the past few years is a dramatic fall in the ages of borrowers. Until recently, typical buyers of the largest homes were in their late 40s, having traded up a number of times before buying a home to see them into retirement.
Now, however, more and more are in their late 20s and early 30s and are typically in consultancy - whether in medicine, financial services or technology. And they tend to have slightly higher loan-to-valuation ratios than their older counterparts, with ratios of 60 per cent or more commonplace.
Very few are first-time buyers, according to bankers - and those that are generally have returned from abroad and have owned property elsewhere, although there was one genuine first-time buyer in Carrickmines last week.
Most earn large amounts of money and have regular incomes of more than £100,000.
According to the lenders, many of these borrowers are choosing to repay their loans at variable rates despite their massive exposure to a rise in interest rates.
Many of the loans also tend to be with the banks rather than the building societies who are generally reluctant to lend such large amounts of money. The borrower will also tend to have a track record with the bank and perhaps other loans.
Until recently, a substantial number of those buying £1 million homes tended to be returning from abroad. However, last week's sales were predominantly Dublin-based, reflecting the large numbers of millionaires created by the booming economy.
As a broad rule of thumb, the banks will lend up to half of a person's net income once it exceeds £100,000. That means someone with a net income of about £5,000 a month, or about £100,000, would be able to borrow almost £400,000 as that would be broadly a £2,500 repayment.
The banks insist that they are well covered in the event of a downturn in the borrower's fortunes. Most have substantial investment properties and one of these could always be sold, they note. On top of that, many are planning to sell their businesses or are relying on an inheritance coming through.
BUT lenders question these loans. Many of the families also tend to have lifestyles to match the homes. Even the grocery bill can be far higher than that of a more modest family, while exotic holidays and cars also account for large portions of take home pay.
They also point out that the logic is fine while the economy is booming but a downturn could make businesses, and indeed investment properties, particularly commercial property, a lot harder to sell.
