Property statistics are all very well, says Michael Fiddes, Head of National Sales for Strutt & Parker, but there is no substitute for up-to-the-minute, local expertise.

Home owners tend to keep a beady eye out for any data that is fed into the national media about property prices - sometimes obsessively so. Among the best known, the Nationwide Building Society and the Halifax produce regular snapshots of annual price movements, while the Royal Institution of Chartered Surveyors (RICS) producing a monthly housing market survey that often makes headlines - particularly when it suggests the news is bad.

Our agents are very used to clients quoting the latest headline numbers at us and expecting us to take them into account," says Fiddes. "But the truth is these surveys have significant failings and often do us and our clients few favours."

The Nationwide survey takes in the whole country, and is also several months out of date by the time the figures are released. "The market can be a lot more sophisticated than what a blanket survey will reveal," says Fiddes. "It can change quickly in subtle ways that such a survey will not identify. Because a large snapshot is not sector specific, it is hardly relevant to Strutt & Parker at all, and our core business of the £750,000 - £3 million country market."

The RICS survey is simply compiled from estate agents suggesting how they think the market is doing at that moment and in the immediate future. "The sample size is small and the impressions given are somewhat anecdotal," adds Fiddes. "It can be indicative, but it can also depend on the state of mind of the person filling in the survey in ways that may not be broadly representative. Too much weight is given to it."

The real problem is the effect that these numbers have on confidence - often wrongly. "It can lead to buyers and sellers sitting on their hands when it is not in their own best interests," says Fiddes. With fewer transactions taking place in the current market, the numbers can be particularly unrepresentative and unhelpful. "To take a single illustration of the difference in the market - in East Anglia there are too many buyers chasing too few country properties. Elsewhere it is the other way round. A decent estate agent will have their own reliable data that they act on. It will be up to date, and it will be local.

"We look at local transaction rates, how many applicants there are per new instruction, the number of viewings before we get a property under offer - from that kind of immediate data we can fine tune our approach to marketing in a particular area."

"We are always looking to use our data more intelligently, and we are currently introducing systems that will do that, both for our use and for the benefit of our clients. There is a big difference between advice, and intelligent advice."