Property: Harsh words exchanged for deeds: Buying and selling can bring out the worst in customers as well as estate agents, says Anne Spackman

The description 'rude, ignorant, unscrupulous and at times downright dishonest' appears at the start of Slippery Customers, a book on estate agents. It is a description that may strike a chord with many buyers and sellers, until they realise it refers to them.

Less generous is the motto adopted by one corporate agency: 'buyers are liars'. Another agent says: 'The general public of this country are by far the most devious, fickle, unbelievable set of people you can ever come across.'

From the other side of the negotiating table is the story of an exasperated seller whose agents put out inaccurate details about her house. They failed to correct them over a long period, printed the particulars without the promised photographs of the interior, did not accompany prospective purchasers to the house, lost the house key, borrowed another and failed to return it for two weeks - and then, having sent round very few viewers over a nine-month period, wanted a withdrawal fee of pounds 100 plus VAT. 'I would rather go to jail than pay them,' the seller concluded. She changed to another agent who sold her house in a month.

This story highlights one of the strongest themes in Slippery Customers: that the public is largely unaware of the huge difference between a good and a bad agent, and has no way of identifying which is which other than by a lengthy process of elimination.

Why not have a Good Estate Agents Guide, which would have the same impact on estate agencies as good food guides have had on restaurants? That is one question raised by the authors of Slippery Customers, Michael Clarke, David Smith and Michael McConville. Another is: why doesn't Which? inspect estate agents as it does garages?

The latter seems a good idea - except that I fear most agents would suss the inspectors out pretty quickly. Inspectors would need a real property to buy or sell in order to judge an agent's ability to secure a deal.

The authors began with a stereotypical image of the estate agent: 'A combination of smarminess and arrogance, an unctuous solicitude masking a ruthless manipulativeness in the drive to complete the deal and earn commission.' Estate agents will be relieved to hear that by the end of their study Messrs Clarke, Smith and McConville come to the conclusion that bad agents are in a minority. More important, their survey of members of the public reached the same conclusion, with three satisfied customers for every one dissatisfied.

The book is based largely on the property market in 1992, the worst year of the slump. This was also when many insurance companies and building societies had bought up independent agencies. The research showed these 'corporates' did a less satisfactory job than independents, but in choosing an agent the public did not differentiate between the two types of agency .

The major difference is that the corporates are in business to sell mortgages and insurance policies as much as they are to sell houses. The people most likely to buy their financial services are buyers, yet it is sellers who are the agents' clients and who pay their fees. This leads to a potential conflict of interest.

'Where vendor and purchaser could be sold mortgages and insurance, the potential commission income for the business was pounds 2,000- pounds 3,000 against an average pounds 500- pounds 1,000 from the sale of a property,' the authors point out.

The agent gets commission for passing on buyers as potential customers to the financial services staff. In the course of their business the financial services department extracts from the customer details of how much he or she can afford to pay. This can be passed back to the agent, who then knows if the buyer can be pressed to make a higher offer.

If a buyer refuses to discuss his financial circumstances, his offer is likely to be presented to the seller in a poor light by the agent. A remark such as 'I can't tell you anything about him because he won't tell us anything' makes the buyer sound suspicious.

In one corporate estate agency, agents were required to pass on information about both vendor and purchaser in every sale, and the financial consultant was expected to get at least one mortgage out of it. If he failed three times, he got a warning. The fifth time he was sacked.

In practice, corporate agents were more often found guilty of incompetence than exploitation. One risked boring clients senseless with sales patter. Another, asked what fee she would charge, was unable to work out 1 per cent of the asking price plus VAT because she had forgotten her calculator.

Reading the book is a good education for anyone about to enter the property minefield. When choosing an agent, one-third of all sellers asked for only one valuation - unwise in view of the inexactness of the results.

Slippery Customers suggests questioning agents about how they have reached their valuation figure and asking about comparable sales of properties in the area. Beware those who ask you first what you are expecting to get: they are likely to go along with you, however over-ambitious your price, in order to secure your business. Do not repeat the mistake made by one buyer, who confided to the agent that he was going to offer pounds 30,000, although he could go up to pounds 31,000 if necessary.

The authors found little evidence of serious malpractice, although some agents said they had been offered backhanders to secure properties for customers or to get them on the cheap.

The book concludes: 'If the public perceives agents as doubtful characters . . . agents equally view the public with a mixture of amazement, frustration and antagonism for their persistent, though of course not universal, tendency to be rude, fickle, unscrupulous and, indeed, dishonest.'

'Slippery Customers' is published by Blackstone Press, pounds 19.95.