Before you spend one penny on valuations, surveys and mortgage applications, here’s a failsafe way of checking the achievable rent level for yourself that doesn’t rely on anyone else’s opinion (or indeed for checking rent levels between lengthy tenancies).

Step 1

Once you’re certain you know the area well enough to make comparisons, find out which local paper covering the area that you’re interested in has the largest ‘Property to Let’ section. In major cities, this will probably be a freebie like Loot. In other towns, it may well be a local paper with a good track record. Get hold of a couple of weeks’ back editions – you’ll need at least two to three weeks to make this work.

What are you looking for?

Ideally, find a property that resembles the one that you’re interested in and find out what kind of money other landlords are asking for similar sounding units. Buildings that only ‘work’ when everything’s running brilliantly often rely on over tight margins.

Will careful research help reduce the iniquitous voids?

Yes. It’s possible to be always full (or as near as makes no difference). In fact it’s standard independent’s practice. We don’t want empty property hanging on for the sake of a marginal rent decrease (see below).

How to calculate using the landlord’s 13-month year

Landlords should only ever use weekly rents – if you don’t believe me read London’s glossies and see how established agents have always advertised. Advertised weekly, a £100 p.w. rent generates £5,200 – advertised at £400 per month it generates £4,800 – a month less. Set weekly rent and, if tenants want to pay monthly, multiply by 52 and divide by 12.

Step 2

Watch out for the same units advertised week after week. They’re too expensive, wrongly located, badly presented – or possibly all three. Holding reasonable quality investment property that doesn’t shift quickly means you’ll need to tweak something.

Step 3

With perseverance, you’ll find similar properties at similar rents. If similar properties are cheaper – adjust your expectations now.

Are they advertised once or twice then disappear? Excellent. That means that they are probably let. But don’t assume that. Call or email the landlord and ask. Pretend to be a tenant or be honest. Every independent landlord’s favourite three words are: ‘sorry, it’s taken’.

If you’ve honed those people skills, you might try engaging the landlord in a chat. Where exactly is this building of theirs, etc? Play it by ear.

Step 4

By fair means (or foul) find a way of getting hold of the address of comparable properties. Landlords sometimes have to be quite creative about how they research. Address in hand – visit.

What to look for

Look for ‘points in common’ with the building that interests you. Adjust your rental expectations up or down accordingly. Better bus routes here? Adjust the rental expectation down. A bit scruffier than your proposal? – adjust up again. This sounds like a lot of palaver, but it isn’t really. These things take an odd half hour but they’re vitally important for what is a huge investment risk.

Appraise honestly whether similar buildings match your expectations. If yours has more plus points, you may be able to ask for a bit more rent, or vice versa. Rental valuation is a fairly imprecise business, despite what agents say.

How effective is this?

Small tweaks to rent can make an enormous difference to demand. Get rent levels too high and you’re in for a rough old ride. Get them too low and you’ll lose money. Get them right and you’re ready to rock and roll.

The downside of knowing the reality

Once you’ve seen similar properties some of you may find that your hopes have been dashed. Perhaps you need to change tack a bit. Maybe a few streets can make the difference you need. Should you choose a different type of property?

Forget what you’ve read – landlords with modest portfolios start tearing their hair out when voids take hold.

The upside of knowing the reality

If you’ve managed to find a good match and have confidence your sums are about right, you’ll want to move forward.

Step 5

Place a mock advert. That’s right – advertise a building that you haven’t even bought yet for the rent you’re hoping to achieve. The car industry has done it for years but call it ‘Ghost Ads’. Advertise before you pay a penny for fees or surveys. This is the only way to sidestep the hype. (For details on how to word advertisements see Lesson 6: Advertising.)

And then wait to see if the phone rings.

How many calls should a single advert generate?

Take it from me – each unit will take several interested callers per advert. I’m finding that I regularly need two or three viewings – and three viewings means at least five calls because not everyone who calls will be interested or suitable.

Oh and by the way, don’t include agents who call up in response to your advert, they don’t count but they do call – all the time. Ignore them. You’re tallying genuine tenants who are actually looking to rent somewhere right now.

Now this suggestion always makes novices blanch – but it works. Every time. And before you start panicking about what to say to callers I’ve already told you the independent landlord’s favourite phrase: ‘sorry, it’s taken’.

Don’t pay out a penny until you’ve had chance to advertise twice and had a fair response both times.