Ali Baba had “open sesame”, magicians have “abracadabra” and now I’ve found my own secret magic words, writes blogger Dan Wainwright.

The spell works on almost every single person to whom it applies and the result is more awe-inspiring than any stunt David Blaine could pull off.

My secret magic words must be delivered with a nonchalant shrug of the shoulders. Act like a French baggage handler who has just sent your suitcases to Bangkok instead of Birmingham.

With a semi-sympathetic downturn of the lip and both eyebrows raised in resignation you need merely utter this: “I’m sorry, I just rent this place”.

The result is incredible. For a second the doorstep salesman processes what you’ve just said. It wasn’t expected. It wasn’t in the plan. He would have been ready for you to say you weren’t interested in double glazing, a new security system, conservatory, patio or landscape gardening.

All those refusals would have been met with a pre-prepared argument, rehearsed and honed to perfection to convince you that you need what he has.

But tell him you aren’t the owner of the property, aren’t authorised to make decisions on any big changes to the infrastructure of your home and his sails lose wind quicker than your nan after her first curry.

There’s no sale to be had. There’s no point leaving a card. There’s no mum or dad to call back and see later. Tenants renting privately are completely untouchable and are useless to the door to door seller.

The only ones my magic words don’t seem to work on are those smartly dressed young men from N-Power who seem obsessed with trying to get me to change my energy supplier. It takes a little more work to tell them that even though I pay all the bills any changes of supplier have to go through my fictitious landlady.

They also don’t work on doorstep missionaries who come to spread the Good News but, agents of The Lord aside, for a set of magic words they’re better than anything Paul Daniels could come up with.

You’ll feel guilty for fibbing, but not a lot.