Does it make sense to buy property? Halifax said this week that house prices are falling at the fastest rate since the crash of the early 1990s. Will today's buyers become trapped in negative equity? Patrick Collinson asks the pundits: are you mad to buy a property right now?

Sarah Beeny, presenter of Channel 4's Property Ladder

"No, you're definitely not mad to buy at the moment. You have to look at it all relatively. The reality is, people talk about a dip in the market but if you are buying a home today you are going to be in it for five, 10 or 15 years.

"Over that sort of time period it is just not going to be a problem. Even if your home does come down a little in value, that just means the next one you buy will be cheaper as well."

She says that potential buyers are in the grip of irrational fears. "Interest rates really aren't at that high a level and it's quite a different economic climate to the early 1990s when rates were at 15%. People aren't in a position where they have to sell because they can't afford the mortgage."

She warns firmly against trying to play the market.

"I think you would be a right idiot if you sell now and try to make a profit by buying back later. I know people - even quite clever guys - who have tried to do this in the past, believing that prices were at a peak. Within six months they couldn't afford to buy back the flat that they had sold."

But the true idiots, she says, are those who are tempted into investing in buy-to-let properties at this stage of the market. "I have thought for some time now that buy-to-letters are bordering on the mental, buying properties on yields of just 3% or 4%."

There's no sign of any downturn in the market for TV property programmes. Beeny has recently been shooting a new series of Property Ladder for broadcast early next year and even if interest in property does dry up, she has an alternative career up her sleeve. She's the founder of the UK's fastest-growing dating website, mysinglefriend.com which now boasts more than 150,000 users.

Fergus and Judith Wilson, Britain's biggest buy-to-let investors

"The prices of flats are dropping." Photograph: Martin Godwin

Fergus Wilson had just returned from a property auction when Guardian Money rang on Thursday this week. "I bought a two-bed house about an hour ago for £119,000, and I'm hoping to get hold of another one that just missed its reserve price," he says.

"I bought five houses from Wimpey last week and paid £153,000 each."

All are in the Maidstone and Ashford area of Kent where the two former maths teachers have built a huge property empire valued today at around £250m.

Clearly this is not a man who thinks we are on the verge of a property crash. "We own a total of 811 houses, and it should be 812 by the end of the day," he says cheerfully. But he only buys houses. He never buys flats, which he says are crashing in price and will continue to do so for years to come.

"The prices developers who advertise in the newspapers are giving are pure fantasy. The prices of flats are dropping, dropping and dropping. There are some flats in Maidstone which went on the market at £240,000 relatively recently which are now being offered to me at £137,500. I wouldn't buy them even if they were down towards £100,000."

The only way to ensure future capital gains, he says, is to buy two-bed and three-bed houses. The problem, he says, is that local planners are only giving the go-ahead for one and two-bed apartment blocks where there is already a glut of supply.

"There was a Persimmon development in Ashford where I bought eight two-bed houses at £130,000 each in 2004. The rest of the development were all flats at £132,000 each. The houses have since gone up in value to £180,000 each but the flats are now selling for £127,000. The estate agents in Maidstone and Ashford are refusing to take any more flats on to their books. I'd advise anyone not to buy flats; you just can't let them. They have built far too many."

He has been approached four times by wealthy Russian investors over the past year keen to buy his entire portfolio of properties. So far he hasn't sold out, but says he will if the price is right - but that price is likely to be north of £250m.

Gary McCausland, presenter of Channel 5's How To Be A Property Developer

McCausland: long-term outlook is good. Photograph: Channel 5/Andres Reynaga

McCausland is both a TV presenter and managing director of a property development company, and fears that some of today's buyers could find themselves in negative equity next year. "Over the short term, over next year, you could see some price falls," he says.

"But that doesn't mean you're mad to buy a property. Over the longer-term, property will remain one of the best things you can buy.

"You can always make money from property in any market - you've just got to be careful to buy at the right price," says the author of How to Make a Million From Property.

The key is to buy from a motivated seller - someone who really needs to sell or perhaps a repossession, he says. "In Leeds, Birmingham and Manchester, there is a huge over- supply of flats, and in Northern Ireland, a lot of investors have lost out as prices have fallen over the past seven months.

"But next year you are going to see more rate cuts and that should stabilise the market. There's not going to be a crash and the British obsession with property is not about to go away."

Davis was the gloomiest pundit we spoke to. "Don't touch property with a barge pole. Over the next year house prices will go down by 5-10% and over the next four to six years they will fall 30-40%.

"It's a natural market movement - when a market goes up 200% in 10-15 years it can reasonably be expected to retrace 30-40% over a four-year period.

"I'm very confident that in a few years people will be able to buy properties for prices they can currently only dream of."

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