Could your tenant actually invent a break-in at your property? It sounds bizarre, but this seamy side to the (otherwise sunny) world of buy-to-let is rather more common than you might think.

Julia Rose, landlady of a three-bedroom house in east London, has recently had two “break-ins” in successive tenancies, even though she knows her house is well-protected and there was a distinct lack of evidence of forced entry on both occasions.

“I have no proof at all that they were inventions, but I was inclined not to believe either of them,” she tells me. “In the first incident, my tenant said the burglar came in through the front door, which has mortise locks. When questioned, he changed his story and said the thief came in through the window, which is fitted with proper locks. Either he had left the windows unlocked, which would affect his insurance, or he was inventing it — I don’t know.

“He said he had his television, mobile phone and computer stolen: stuff that doesn’t get nicked much these days because the resale value is so low. But he was going back to his base in Paris, so it wouldn’t matter to him.”

It did to Rose: the incident added £100 to the insurance premium of her house with Royal & SunAlliance, which meant the next time it happened, she was even less thrilled.

“The tenant claimed she was burgled while in the bath. She said the thief came in through the upstairs window. My agent went round and found nothing wrong, so she was either lying or had left the windows open. She said her bag, phone and laptop had gone. It struck me as quite coincidental.”

Jane Wenham-Jones, a novelist whose scrapes as a landlady in Ramsgate have provided fodder for a couple of her books, knows all about burglary claims by tenants. “I had a tenant who claimed three times that her front door had been bashed in,” she says. “Each time, I had to pay for a new door and fit new locks. I suspect it was an ex-boyfriend. It didn’t put up my building insurance because I didn’t report it. I just paid for the repairs.”

With another flat, she did claim — but then found herself being refused insurance when it was time to renew. “An entire boiler went missing: disconnected and removed,” she says. “I’m quite sure it was the last tenant that took it. I had to claim for a replacement, which cost about £800 and I had to change insurance companies, with the new company charging me £200 more on my premium.”

Her advice? “Choose the right tenant, but remember that getting a good one is the luck of the draw.”

Of course, some tenants do suffer genuine burglaries. You can keep the possibility of this very low, advises Harry Johnson, a landlord with nearly 50 houses and flats in Manchester, by having “security like Fort Knox”. As he says, the security of your property is up to you, the landlord.

“All of our flats, regardless of what storey they are on, have burglar alarms. They all have reinforced front doors. As we own blocks, not just individual flats, we ensure that the locks to the main doors are Magna locks, which will hold back four tons of weight. All of our car parks have automatic gates with fobs for our tenants.”

What about window locks? “They don’t hold much back for more than a couple of minutes,” Johnson says. “The average burglar doesn’t care about the state of your window. He will use a spade or a flagstone to get in. On vulnerable storeys, we install wrought-ironwork around the window, which stops it from being opened more than 6in.” Isn’t that a fire hazard? “We have smoke alarms in every property,” he says. “And protected areas for escape in each building. Also, our front doors allow locking with a deadlock only from the outside, so you can’t lock yourself in by accident.”

But what about landlord’s insurance? I get on to Jonathan Morgan, boss of the eponymous estate agency in Leeds. “It’s all about getting an insurance policy that recognises that your property is let,” he says, pointing out that buy-to-let properties are attractive targets.

“Rented houses are quite obvious to a thief. Things like ‘To Let’ boards, unkempt front gardens, different lifestyle patterns: these all indicate a rented house. A broker will give you a series of recommendations at the outset. If you don’t do that, and you are burgled, you will struggle at the point of claim.”

What sort of things do insurers insist on? “Kite-marked, British Standard, five-lever door locks. Proper locks make escape for the burglar much harder. They can smash a window to get in, but because of DNA testing they don’t want to risk clambering back out with a whole load of stuff.”

“It is vital to get the right insurance,” says Sue Fitz-Gibbon, senior partner at letting agency Fitz-Gibbon Residential, which has about 1,500 clients in central London. “We are all a bit laissez-faire when it comes to insurance. If there is a burglary, any claim will relate to whether the tenant has contents insurance. But how and why the thief got in will also need to be investigated.”

And do check how much your own insurance actually covers. As Fitz-Gibbon puts it: “Wood-stripped floor can be worth an awful lot, frankly.”

Buy-to-let advice from Rosie Millard can be found online at www.timesonline.co.uk/investmentproperty

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