Shortly after they moved in, interest rates started to increase and haven't stopped since. The mortgage was 520,000 over 30 years and Mark and Tara availed of Bank of Ireland's discounted variable rate for the first year. This started off at a low 2.69%, giving a monthly repayment of 2,106 before tax relief.

Twelve months later, their discounted rate has expired and interest rates have jumped on five separate occasions, with another hike due to bite over the coming weeks. Instead of paying 2.69% interest, Mark and Tara are now on 4.64%, while their repayments have soared to 2,678 a month.

As young professionals with healthy earnings, they are not yet alarmed as their incomes have kept pace with the rise in interest rates. But they want to make sure their mortgage remains good value for money, especially in a market where lenders are having to coming up with sweeter deals to hold on to their customers. They also want to stay on a variable rate to allow themselves the flexibility to make additional repayments as funds allow.

Mark and Tara approached Liam Ferguson of Ferguson & Associates, a multi-agency intermediary and mortgage intermediary, to examine their options.

For starters, he advised them to contact Bank of Ireland, explain that they are considering moving their business to a more competitive lender and ask for its best offer to retain the business. It offered a tracker variable rate of 1.25% over the European Central Bank's base rate, which was an improvement over the existing rate.

"While the offer of a better tracker rate was an improvement, it certainly wasn't the best in the market, " says Ferguson.

He arranged to switch them to a tracker rate of ECB plus 0.75% with First Active. This rate stands at 4.25% at present, and that's including the most recent ECB rate increase. While First Active restricts the availability of this rate to those whose mortgage represents less than 80% of their home's value, property value increases make it accessible to most people who bought over a year ago.

Without changing the duration of their mortgage, Mark and Tara's repayment dropped to 2,558 per month, a saving of 120 over their present repayment.

They also bypassed the further increase in December which would probably have added another 75 or more onto the monthly cost. "In effect, going from 1.39% above ECB to 0.75% above ECB allowed them to roll back the last two interest rate increases and then some, " says Ferguson.

While going through the process of re-mortgaging, Mark and Tara caught a lucky break. They had already agreed that Ferguson would pay their legal fees and valuation cost for the switch on their behalf, so the only cost of moving mortgage should have been the stamp duty on the mortgage deed at 0.1% of the new mortgage amount, or around 500.

However, while they were waiting for their loan offer to issue, Brian Cowen abolished stamp duty on mortgage deeds in the most recent Budget, with effect from 7 December. So they paid no fees whatsoever for moving their mortgage. Having agreed their new interest rate, the young couple decided to take the opportunity to make further cost savings on their mortgage.

"They had been paying 254 per month each into SSIAs for the last couple of years, " says Ferguson, "and with these maturing in January 2007, they were looking to continue the savings habit and find a good home for the proceeds. Some of the lump sum will be spent on a holiday and a new flatscreen television, a course of action I wholeheartedly endorse . . . having spent five years diligently saving, you may as well enjoy some of the fruits of your efforts.

However, to continue the habit, they've agreed to pay an extra 250 per month off their new mortgage, which will knock around four and a half years off their mortgage and save them 68,000 in interest. The other 250 they will continue to save for a new five-year period."