Seven and a half months

... is the average time it takes to sell a house. But if the price is right, you are much more likely to make a quick sale

The Burke Special, one of television's early science-made-friendly programmes, once demonstrated how humans look at each other by following the pattern of a woman's eye movement across a picture of a stranger. First the eye went backwards and forwards dozens of times across the face, then it followed the outline of the body, and finally it filled in the rest. What would happen if they were to repeat the experiment with a set of property details? The eye of the potential buyer would probably go to the picture, the address, the price and then - possibly - the bits in between. The decision on whether to view, never mind offer or buy, would most probably be based on those three factors alone.

These are difficult days for sellers. According to a new report from Black Horse Agencies, based on 100 of its offices, it now takes on average 22 weeks to find a buyer and a total of 31 weeks to complete a sale. The total figure varies across the country, from a low of 23 weeks in the eastern region to 37 weeks - almost nine months - in the north-west.

These figures would not apply to the lucky owner of an attractive period house in good condition in a desirable location. The few that come up for sale still get snapped up very quickly. Gosford House is a good example. An eight-bedroom Georgian property in four acres outside Exeter, it was sold by Strutt & Parker for more than its asking price of pounds 325,000 within a month.

But for the vast majority of sellers it is a long slog. They can do little to change the location of their house, apart from the rather ludicrous trick of describing it as being on the borders of somewhere smarter. But pictures and price fall well within their control. In today's nervous market it is vital to get both right.

The latest authoritative report from estate agents belonging to the Royal Institution of Chartered Surveyors could not be blunter. It says: "The overriding message is that accurate pricing is essential for a successful sale. Only realistically priced property receives attention from buyers. Overpriced houses are spurned."

The problem with words such as "accurate" and "realistic" is that they are subjective. Many buyers still retain in their minds the heady value of their house in the boom days and are reluctant to accept it may be up to 30 per cent too high. They are only too willing to believe the wildly over-optimistic estate agent who agrees with them because he is desperate to get the instruction. With business so thin on the ground, over-valuing is rife. The result is that the house sits on the market for months and is viewed by buyers as tired goods.

When Trixie Offord had to sell a two-bedroom flat in Stoke Poges, Buckinghamshire, following the death of her mother, she called in a number of estate agents. All told her that the figure of pounds 66,000 she had in mind was too high, but a couple said it could be worth a go. "I was handling the sale on behalf of three of us and it was up to me to get the best price," she says. "I went with the agents who thought I might get the higher price if I stuck it out."

After a couple of months and no offers she went back to Hamptons in nearby Gerrards Cross, which had originally suggested a price of pounds 59,950. She agreed to drop her price to pounds 62,500 and two weeks later she sold for pounds 59,950.

Hamptons handled a similar case in Gerrards Cross, where a four-bedroom house had been on the market for a few months at pounds 285,000. They valued it at pounds 250,000-pounds 260,000. The vendors agreed to drop their price to pounds 270,000 and it sold six weeks later for pounds 250,000. "There is a message right through the market," says John Webb of Hamptons. "If you get your price right you are going to sell. If you have got something extremely special you can still get a very full price."

But how does a seller know which agent has got the price right? One good rule seems to be to ask how they reached their figure. The best will give you evidence of similar houses they have sold in the area.

Colin Fitzgerald of Hamptons in Wimbledon went to value a four-bedroom detached house four doors down from a five-bedroom one he had sold a few months earlier. The larger house had gone for just under pounds 300,000 and he reckoned this one would go for around pounds 275,000. It went on the market with another agent for pounds 325,000 in April. The price has just dropped to pounds 279,000. "If it had gone on at pounds 279,000 it would have been sold by now," Mr Fitzgerald says. "By going too high they missed the spring market and had to sit out the summer."

The London chain Foxtons, which has a reputation for aggressive selling, says you should have a very good idea of your property's potential within the first three months of it being on the market. "This is because agents get their keenest buyers around first, eager to pounce on something new," says Karen Hancock. "You should have received at least one offer in this time and certainly a second viewing."

If there have been plenty of viewings, but no offers, it normally means the price is too high. The same is true if you have had a lot of interest, but the offers have been way below the asking price.

If there have been very few viewings, it may mean you have the wrong agent. They may not have access to the right kind of buyers or they may have got the price or the marketing wrong. Karen Hancock suggests, however, that it may be a mistake to go on everyone's books, as it suggests to potential buyers that you are getting desperate.

When it comes to pictures, many buyers feel they must put up with whatever the agent produces. For most sellers this will mean one small picture of the front of the property. In some cases - even at the top of the market - the pictures are not even in focus. If you think your garden or your interior is a far better sell than the front, it is worth pushing for that to be shown - or for there to be more than one picture.

BEFORE YOU SELL

Do

Make your house look as attractive as possible for the photograph. Paint, plants, clean windows all help; no dustbins or discarded mattresses by the door

Make the house available to view as much you can and keep out of the way when prospective buyers come.

Don't

Choose an agent on the basis of the highest valuation

Leave dirty dishes in the sink, dirty clothes on the floor or beds unmade. A scruffy house will put off buyers. Presentation is crucial

Move out before you've found a buyer: every empty week is likely to knock a few pounds off the price as the house gets mustier and the garden more overgrown.