What are we all in this for? Tricky tenants, slippery agents, godforsaken building sites: yes, the whole buy-to-let game. Pensions, that’s why. We’re all doing it so we don’t end up facing our maker from the vantage point of the gutter. So if the average age of the buy-to-let investor is 45, what will happen in 20 years’ time? First up with the crystal ball: Yolande Barnes, head of residential research at Savills estate agency. Because so much buy-to-let investment is the same type of building (two-bed new-build) in the same place (the city centre), Barnes is concerned that rather than provide a pension payout, these areas will have an inbuilt price weakness because they will have never matured into family-led normality.

“They will have always been predominantly rental,” she says, “and so will have values based on rental worth rather than capital value.”

A transient population could mean a dearth of community institutions — schools, doctors, and so on — which in turn might make an area unpopular with the buying market. Somewhere branded “rental land”, in other words, won’t have kept pace with property in more conventional areas, and investors wishing to cash in after a couple of decades of rental might catch a cold.

“It could be an issue if investors have bought thinking they have invested in owner-occupier capital values, rather than rental capital values,” warns Barnes, although she acknowledges this is not so with London, where property demands are constantly high.

Another problem facing the capital worth of the average buy-to-let, says Barnes, is that if we all decide to cash in at the same time, the market will be flooded with tired-looking flats boasting chrome kitchens and Starck “bowl” basins. “And a few sales in the market for the same type of property in the same place will drive down values.”

Philip Stewardson, a Midlands-based professional landlord who started buying in 1994, agrees. Stewardson, whose £9m portfolio consists of more than 80 properties, says he’s started seeing the effect already.

“The market will be flooded with two-bedroom flats,” he says. “In city centres people will start doing it quite soon, because they are worried about it holding on as an investment. In Birmingham, people are already too scared about capital values falling to keep on buying more.”

What rot, says Frank Harris, who runs the eponymous central London estate agency. “Buy-to-let investors will make money. They will all make money. Some will sell now, and some will choose to hang on. But over 20 years they will all have made money.”

What about wear and tear? “You put in a new kitchen and bathroom and bingo! You’re away. Look at the cyclical nature of the market. Twenty years is enough time for troughs and peaks. I would be amazed if people don’t make a reasonable capital increase on what they have. All you can do is look at a historic graph of prices, and calculate that over a 20-year period there will be capital growth. There is nothing else to base it on.”

Let us then speak to the average buy-to-let landlord. I ring three of them. The first is Oscar Lennox, who has a clutch of flats in Clarence Dock, Leeds.

“Selling up in 20 years? I’m going to sell up in 20 weeks, to be honest,” grumbles Lennox. “Prices haven’t moved for two years and rents are coming down. Effectively, I am subsidising my tenants to maintain my properties. I bought these flats in 2002 for £126,000 and £128,000, with 80% mortgages, and I’m putting them on the market for £126,000 and £128,000. I’m happy to be leaving the buy-to-let world. I’m going to look to the stock market for my pension.”

Robin Lawton has 14 houses and flats in Southampton and one in central London. His outlook is a bit less Armageddon- like, but he’s still not hanging around.

“I’ve already started relinquishing my properties, but not in one fell swoop,” he says. “I’m going for a drip-feed approach. If I see the right opportunity, I’ll sell. Selling one a year also eases the pain of capital gains, because of the annual allowance. I’m going to operate slowly and progressively, depending on what the market is doing, dealing with my portfolio in stages to assist cash flow and my standard of living.”

Barry Martin, a wine importer, has nine properties, also in Southampton, and he isn’t budging.

“My view is ‘never sell’. If I want large amounts of cash, I will remortgage,” Martin says. “For a pension, I will use rental income. Why kill the goose that lays the golden eggs? Unless the entire property market changes, the properties will go on increasing in value. So you can always take something off the top.”

Marc von Grundherr, a rental specialist with Benham & Reeves, a residential lettings specialist, is on Martin’s wavelength.

“Why sell off your assets when you retire? Keep the assets and have the rent come in as an income stream. That’s the beauty of buy-to-let as a pension. Upgrade the decor, and remember that if you have bought something decent in the first place then it will remain a property of good quality. It’s a no-brainer.”

Meaning that the excellence of your property 20 years back will dictate what you do in 20 years time. Probably.

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