At a wedding the other day, I was really put in my place after banging on, as you do — or at least as I do — to another guest about my fabulous property portfolio, which comprises three flats. My companion indicated that he had also dipped his toe into the warm bath that is buy-to-let.

“How many flats do you have, then?” I inquired, conversationally.

“Thirty,” came the reply. It was a humbling moment, a moment when I realised that I was, by comparison, a complete amateur in the field. But when is the critical mass reached; when do you arrive at “professional landlord” status? I’m quite clearly not there, but then neither is my friend Susan Browne, who has five flats, all high-end, all in west London, with a combined value of about £4m. “I would call it a pension fund,” she says, speaking from Sydney, Australia, where she is holidaying. “Buying property almost started by accident for me, and I was never able to give it the time to build into something really big. Pity. No, I wouldn’t consider myself a professional landlady.”

In Browne’s view, that status comes when you need more than two hands to be able to tot up your portfolio. “Professional landladying begins when you have about 10 properties,” she says.

Background

• Tales of a landlady: Tax reforms

• Into the sunset

Background

• Tales of a landlady: Degrees of success

• Tales of a landlady: It pays to shop around

• Tales of a landlady: Residents only

• The ties that bind

• How low can you go?

Background

• Tales of a landlady: Avoiding the agents

• Tales of a landlady: In the dock

• Tales of a landlady: the age of reason

• Tales of a landlady: Heroes and villains

• Tales of a landlady: High maintenance

Background

• Back to the ’burbs

• A waste of energy?

• Tenants like gardens, but not tending them

• In the doghouse

• Parking mad

It’s eviction time

Can investors profit from the rise in repossessions?

• It’s eviction time

Background

• Do property workshops work?

• A letting gamble

• Spread betting

• When buy-to-let turns from a hobby into a living

Tales of a landlady: Persistent complaint

How can lettings agents justify annual renewal fees, asks Rosie Millard

Background

• Landlords: halo or horns?

• Bidding wars

• Time to quit the ring?

Background

• Proceeds with caution

• Criminal behaviour

• Tales of a Landlady: One hell of a mess

• Homeowners look to profit in the sun

“Looking at it another way, it’s when you can afford to support yourself from your rental income,” says Browne. “Or, if you are a developer, it’s whether you can support yourself on the capital gain from turning around flats in a very short period. Income is the defining line.

“It’s a jolly hobby, though. It gives me a lot of satisfaction. I love being on building sites.” With that, she’s off for a morning swim.

Next up is Mark Carthy, who has 10 properties in east London, and one apiece in Italy and Switzerland. So, he is well on to professional status in terms of numbers of flats, even though their overall value (£4m) is the same as Browne’s. Indeed, he is on the point of giving up the day job. “I’m a cabinet-maker by trade, but someone introduced me the other night as a landlord, so maybe I am. I still do a bit of refurbishment and kitchen fitting for other clients, but I would like to give that up and become a full-time landlord.”

Carthy has a different opinion of what is the crucial measurement. “It’s about the time your properties take to manage,” he says. “Most of my time is spent getting to know, and getting on with, my tenants. It’s worked for me. I’ve been doing it for 10 years and only once had a problem with a tenant.” The other maxim is that you must never reach a position of stasis. “You have to keep on buying. I’m always looking.”

Furthermore, as a pro, you need a clear strategy. “I only go for older properties,” he says. “I’m not interested in new-builds or off-plan. I know what works for me.”

A sense of assurance helps, too. “I’m confident about finding the right thing. I’m not afraid — after all, it’s the bank’s money you are using. As long as you manage it properly and provide a decent home with modern amenities, you won’t go wrong.”

Does it give him a living wage? “I suppose it does. I make about £20,000 a year in profit. I’m not mortgaged up to the hilt, either. I’d say my leverage (mortgage percentage of the overall property value) is about 40%.” He plans to lower that. “Because soaring interest rates, as in the mid-1980s, could happen again.”

And so I turn to a thorough professional, Lahrie Mohammed, who owns 150 properties in and around Walthamstow, east London. How did he get there? “I suppose I started to call myself a professional when I had about 20 properties,” he says. “I was a full-time accountant. I had a secure income of about £40,000 a year. Being a landlord was a hobby. But then my flats started to take up more and more time. I didn’t want to hire an agent, you see.

“First it was two hours a week. Then it was a day a week, then two days a week. Eventually I couldn’t manage both at the same time. So even though I was afraid to do it, I gave up the day job. I thought that all my problems of time would be instantly solved if I focused entirely on buy-to-let.”

Were they? Of course not. Mohammed now employs one full-time assistant, four full-time maintenance men, “plus 25 others working on various different projects”.

His strategy has also changed. “There is no financial reason now to buy and hold on to property,” he says firmly. “You won’t survive with yields of less than 5%, which is what they are now. You can’t rely on rental income for profit. So you need to go down a different avenue. Buying and selling is the answer. If I have a tip, it’s this: you have to find a way of adding value to a property, with a view to selling it on quickly.”

This is not to say, of course, that Mohammed is about to flog his entire buy-to-let portfolio. Not a bit of it. (Nor indeed, for that matter, should the rest of us). It is just that he has had to modify his strategy, given the way that prices have been rising so much more quickly than rents recently.

Either way, I feel such a minnow by comparison, that I hardly dare ask this property whale how many flats he buys and sells in any given year. “Oh, about 30-40,” he says casually. Blimey.

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

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