9.40am. Open door to young and very small boy, Jeff, who bounds around like an affectionate puppy. Assures me he knows area intimately - "my girlfriend lives round the corner" - and soon gets me as over-excited as he is: "You're looking at loads of money." Effect spoilt by long phone call to his boss: "It's a tricky one." Glean from eavesdropping that boss, like Jeff, has no idea where house is, or its value. Jeff confides he "loves his job". Who wouldn't after six months? Leaves with a whimper.
10.30am. Kevin bangs on door. Looks rough. Explains he was up late watching football. Appears more mature apart from his brace. Sit down for lengthy chat. Kev seems receptive to questions. "How many clients are looking for this type of property?" "Lots", offers Kev. Eventually gives truly tempting valuation and for lowest fee, 1 per cent, so I promise to be in touch.
11.30am. Receive call from mobile phone. Giovanni will be late (football fever again). Finally open door to dour person who shatters all preconceptions about excitable Latinos. Giovanni's lip curls as he looks round. Get sinking feeling, synonymous with mechanic looking under bonnet. Wait for property equivalent of "your big end's gone". Not surprised when Giovanni suggests selling to developers and, naturally, he can recommend some. His valuation is pounds 50,000 less than Kev's. Close door reeling in confusion and determine to seek further advice.
Ian Dickson, director of Winkworth, Shepherd's Bush, says: "You are making a huge financial commitment and must be confident that the agent will do a good job. If he puts you off, will he put buyers off?" He finds the choice of agent "varies dramatically" depending on whether you are buying or selling: "The man might be the biggest creep in the world but if he's got the right property at the right price, and you're buying, who cares?" Some agents may not know their market and will undersell properties. "It's great for buyers but not sellers."
Mr Dickson believes overpricing is more common among agents and finds that many vendors simply choose whoever gives the highest valuation. "It's a common ploy but sellers frequently find that, within weeks, the agent wants you to reduce the price to the figure suggested by the middle man. We get vendors coming to us who feel they have been tricked."
But how can you ensure that your valuation is accurate? Most agents suggest asking for proof of comparable sales. Confirm their accuracy by asking to see property details and make comparisons in terms of location, size and condition. This involves research on your part but it may be worthwhile.
Your valuation may be realistic but is your agent competent? Carol Sutton eventually sold her three-bedroom semi in Surrey, but only after changing agents. "In three months the first hardly sent anyone round to view, and the ones he did send were looking for something completely different," she recalls. So how can vendors minimise inefficiency? Ian Dickson advises: "Go into the office and look at the quality of staff. Inexperienced 17- year-olds probably won't give as good a service as people who know a lot about what they are selling."
He goes further: "Pose as a buyer and see what reception you get. Ring up and say what you are looking for. They may offer to send details but a good agent will talk you through what they have and ask when you want to come and have a look."
Is it better to choose a large chain rather than a small business? "I wouldn't condemn the one-office operation. They may know their area thoroughly and have reciprocal agreements with others, but do check how much exposure they can give your property." Vendors should also be aware that bigger firms frequently move agents around, so their local knowledge may be inadequate compared with that of a small company's employees.
I thin of Kevin and ask Ian Dickson whether fees should form a basis for choice. He warns: "Don't go for the agent who offers to cut his rate. Many have to, because they are scraping around for business."
Someone who isn't scraping around is Gordon Blausten, of the Notting Hill agency Bruten & Co. What makes him estate agent of the year? "My glittering personality I suppose!" He compares choosing a good agent to finding a solicitor: "Ask neighbours and colleagues in the area in which you wish to buy. Test out their local reputation. The agent with the highest profile is not necessarily the best."
He counsels against agents who operate simply as marketing companies. "It works, but they are often interested only in getting the deal done rather than obtaining the best for their clients. We want the best, but not necessarily today. We sometimes advise clients to wait and they may be able to get a bit more."
The National Association of Estate Agents asks prospective members to complete a written test and lays down guidelines. The NAEA is also campaigning for the industry to be licensed.
Gordon adds a cautionary note about pricing: "We work on comparables but also take into account how much people are willing to pay. Prices would never rise if we relied solely on surveyors' valuations." Most agents say that publicity is important, but Gordon is philosophical; "One good negotiator is worth a dozen pages of adverts."
Before choosing an agent: Check that they belong to a trade association; meet the manager and staff; pose as a buyer; look at comparables and check property details; ask how much coverage they will give your property.
Winkworth, Shepherd's Bush: 0181-749 3394; Bruten & Co: 0171-229 9262