In a study of the buy-to-let market, Business Development Research Consultants (BDRC) looked at the “motivations and attitudes” of property investors and discovered that, sadly, we investors are not all that keen on those who are helping our investment work — namely, those who actually rent our houses from us.

Well, we have all had terrific tenants but, again, most of us will also have had grim ones: tenants who bring in undercover rottweilers; tenants who withhold the rent (particularly the final month’s worth); tenants who have a vague or non-existent relationship with the vacuum cleaner; tenants who turn your lovely flat into a knocking shop. A friend of mine even had a tenant who murdered someone in the flat. It all makes great material for dinner-party chat, but in reality is not ideal for a harmonious life.

So how do you pick a good tenant? All the property bibles suggest that getting references is a good start. Personal references, bank references and work references are what you must have before signing up someone for a six-month assured shorthold tenancy agreement.

Speaking to some of my fellow landlords, however, it would seem references are a waste of time.

“Worth about as much as the paper they are written on,” says a friend who owns a clutch of houses in east London and rents them out by the room. My mate — we will call him Tom (he fears his tenants may read this column) — sets absolutely no store by the value of a decent reference.

“Personal references are worthless,” Tom says. “So you get a letter from someone’s parent saying that their offspring is fabulously creditworthy. So what?” I know what he means. I once had a tenant who turned up waving a personal reference from a cleaning lady in Billericay. Who loved him very dearly. Was she going to guarantee that his rent would be paid on time and in full? Probably not.

“The only references I take seriously are ones from the tenant’s place of work,” Tom continues. “I ask for a reference on headed paper. Then I ring up the institution to check the person actually works there.”

Sometimes they do, he finds. Sometimes they don’t. Sometimes the institution itself is non-existent.

How does Tom discover that? “It’s easy. I ring Directory Enquiries,” he says. In the past, he has discovered the workplace is invented, or exists, but only in the form of a domestic home. I had no idea tenants were so, er, creative.

I get on to Brian Styring, a financial adviser who owns and rents out 30 or so houses in north Warwickshire. Does he bother with references? “Ha! Good question. Generally speaking, no,” Styring says.

Why not? “Because of the time and hassle involved,” he explains. “I just ask for proof of ID, proof of where they live and the name and address of the company they work for.

“There have been a couple of times when I should have taken references and didn’t, because the tenants didn’t pay. But, frankly, a reference doesn’t guarantee anything. Even if tenants are working, it doesn’t guarantee they will pay the rent. In general, if you take a month’s rent in advance and six weeks’ rent as a deposit, in cash, then most people will be good tenants.”

Even if they are in work, it doesn’t mean anything. “One of my tenants started out in work but then lost his job,” Styring says. “He failed to pay the rent. It took me four to five months to evict him, because the court process is so slow. The week before the eviction order came, he left the property. But he took all the internal doors and downstairs carpets with him.” Cheers. “No, I didn’t have references for him but, even if I had, it wouldn’t have made any difference.”

Did Styring get his rent back? “No.” Did he get his doors back? “No.”

How do the professionals see the reference issue? “Our line on references is that we absolutely insist on them,” says Ed Phillips, head of lettings at Foxtons in Islington, north London. “It’s no guarantee, but knowing who you are dealing with is very important.

“And if a tenant can’t supply a reference, well, then it immediately rings alarm bells. We insist on references from the tenant’s employer, with details of their salary, references from their bank, and from any previous landlords. It gives us an idea of someone’s financial background and a general overview of the tenant.”

Of course, even the most glowing reference can run aground. “The interesting thing is that some landlords will query a reference from a nurse earning £19,000 a year,” says Phillips. “In my experience, it will be the City banker with the salary of £150,000 who is going to have the wild parties. References are no indication of how well the tenancy will go. All they do is give you something to hang on to.”

That’s it. As Phillips points out: “The only piece of paper worth anything to the landlord is the tenancy agreement. That’s the only thing that will stand up in court.” There you have it. From the horse’s mouth.

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

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