Secret Agent: 'The sweet russian widow turned out to be more oligarch than little old lady'

I recently went to a photography exhibition and came across a photo that perfectly epitomised our industry. It featured a shark and a pilot fish. I think it was supposed to be about mutual benefit. The shark – the greedy estate agent – is prowling the ocean for food, while the little pilot fish – the trusting client – is being taken for a ride.

At least, it seemed the perfect metaphor until yesterday, when the waters became somewhat muddied.

"Oh... my... God." Justin swept into the office, having clearly watched too much Will and Grace. "Have you seen it?"

I stared at him blankly. "What?"

"One of their boards!" he said, gesturing to our rivals across the road. Justin's fascination about For Sale boards makes trainspotting seem a riveting pastime.

"Where?" I said, wearily.

"Outside what used to be Mrs Levitsky's house."

A silence fell on the office as everyone took in the significance – not least me. This property plagued me all last year like a recurring verruca. It had been a particularly dilapidated three-bedroom house owned by an equally dilapidated Russian widow. The trouble was that while she had looked frail and feeble, when it had come to talking money, she was more oligarch than old lady.

Her: "No, this is not enough."

Me: "I think it's quite a reasonable offer given –"

Her: "Pfff. I need more."

Her insistence that, in spite of her house having faulty electrics, leaky plumbing, dry rot, wet rot, a disintegrating roof and a garden the size of a toenail clipping, it was still worth half a million pounds, made it rather tricky to sell. It didn't offer enough of a "margin" to tempt property developers, but was just that bit too much of a challenge for Mr and Mrs B&Q.

Eventually, after a great deal of painful negotiating on my part, she reluctantly sold it to an interior designer called Zac. He filled it with lots of smoked glass and chrome, as obviously befits a property built in 1865, and promised to re-sell it through us when the time was right. Which is why yesterday's discovery came as such a surprise.

"I'm going to ask him why he didn't even give us a look in." One of the wonderful things about Justin is that he has absolutely no shame whatsoever. "Watch him squirm," he said, reaching for the phone.

"I wouldn't," my manager snapped. We all turned and stared. "He did get me round to value it."

Justin looked confused. "And?"

It turns out that our rivals were so desperate for the instruction that they had decided to operate a reversal of John Lewis's policy – if the vendor was quoted a value by another estate agent that was higher than their valuation, they would match it.

And, of course, Zac, driven by innate human greed, couldn't resist this offer. So much for the trusting little pilot fish. And mutual benefit.

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