People buying homes 10, 20 or 30 ago may not have counted on their property rising to the heady values of recent times. But after a lifetime repaying a mortgage, home-owners could now be looking at a substantial profit if they sell out during the current boom and purchase a less expensive property.

Anecdotal evidence suggests that many people are considering the option. AIB's head of home lending, Mr Aidan Clarke, said a number of the bank's customers had traded down. And estate agents Sherry FitzGerald said about 8 per cent of people selling homes last year planned to purchase less expensive property. However, EBS head of marketing, Mr Pat Farrell, said he was not aware of any particular trend.

With many homes now fetching £500,000 or £600,000 at auction, owners may decide to purchase a less expensive property - at £250,000, for example - and take the profit. For those whose mortgage is paid off entirely, the gains are obvious.

But while many lenders do not charge additional fees to people who pay off a variable rate mortgage, those clearing a fixed rate loan will pay a penalty.

People with long-term repayments to make should bear this in mind. At the EBS, for example, customers repaying all or a portion of a fixed-rate loan of between three and five years must pay six month's interest on the amount redeemed.

There are other costs. One mortgage business expert, who asked not to be named, warned that stamp duty and professional fees in a move from a £1 million property to a home valued at £300,000 could cost £50,000. Old furniture may not fit when moving to smaller accommodation, so these expenses should be considered too, he said.

Yet the figures could add up. As ACC Bank's market development manager, Mr Denis Fahy, observed, older people are choosing to sell large family homes to move into smaller, more manageable, apartments. And others are moving to the country from the city, he said.

"The vast majority of people are not in the first flush of youth," said Mr Fahy. With this in mind, he warned that those considering a move should tease out all the options. Selling up to move into a new apartment may offer greater financial freedom and less housework, but gardeners may not relish the prospect of life without the hedge-clippers.

There may also be emotional considerations. People may think they can make a clean break from a lifelong home, but moving out may be difficult when the time comes, Mr Fahy said.

For all that, older, second-hand apartments are available in parts of Dublin most affected by the property boom. This means older people could find property near their children and grandchildren.

One market expert said many people consider downgrading to provide an income above their pension if they take early-retirement.

Others have sold houses to purchase smaller accommodation here and a second home on the continent, said Steve McGettigan, managing director of Sherry FitzGerald subsidiary Mortgage Insight. "It's a lifestyle thing. If you're 60 years of age you're not going to get involved in any kind of risky equity investment. You're not going to get into long-term equity investment."