Hard is the life of a PI. I know because I have donned my Sherlock Holmes hat and magnifying glass?though I forwent the pipe?for the last few days. You see, I came back from holiday to find that my London neighbour is selling her home.

Thing is, whenever a house in my immediate neighbourhood is up for sale, I just have to discover how much it is up for. Understand it is all for the sake of market research, of course. After all, my homes are my greatest?make that my only?investment and I need to track their value over time. And what better way to do that than looking at the asking price of similar homes in the same area?

Since mine is much nobler cause than plain simple property busybodying (as you will all definitely agree), I’ll go to whatever length it takes to find out that crucial bit of information. Not that I had much trouble in the past, mind you. Most neighbours were incredibly obliging. They either told me outright (my favourite lot!) or put clear signs showing which agent was marketing their home. All it took was a casual glance at the appropriate windows, or, at worst, a quick phone call and et voilá! Market intelligence fell neatly into my lap. But not this neighbour, no. She was cagey. She wouldn’t say how much she is asking. No sign outside her front door advertised the selling agent.

This required heavy sleuthing. So I meticulously started tracking every property website to check whether by any chance it was there. Have you any idea just how many homes for sale are available in SW7 for any price range? Well over 200?and that’s just on one website.

In the end, painstaking attention à la Sherlock Holmes served me little (undoubtedly because I had omitted resorting to the all important pipe). My eyes started crossing long before I found the answer I so ardently sought.

Instead, it was a stroke of luck worthy of Gladstone Gander that did it. I was about to leave home when the bell rang.

“Hi, It’s Foxtons here,” said a cultured voice on the entryphone. “We are showing home Such and Such but have been locked out of the main gate. Could you be so kind to open it for us?”

Could I? Of course! For the small price of knowing how much the property was for sale at. And before you think that I have turned blackmailer as well as busybody, remember: It’s all for the sake of market research.