The window-cleaning racket

On the third week of every month, I get a note through my mailbox from my dutiful neighbour, telling me that the window cleaner is due on that Wednesday. In exchange for this note, I then put a fixed amount in an envelope (I won't disclose how much it costs to get one's windows cleaned) and put it through her mailbox, which she then pays to the window cleaner while I'm at work. I don't feel like I get a particularly good deal; because of the building's layout, the window cleaner can't actually clean the windows to my bedroom, and I don't get a discount for this. I'm also not convinced that my windows are any cleaner, so I'm trying to see whether I notice any difference, as I've actually forgotten to pass my money through my neighbour's mailbox these past two months. So far, I can't confirm that my windows are any dirtier than my neighbours'.

I've also noticed that every month, these notes are written on stationery swiped from a different hotel. This month it was quite a snazzy Swiss hotel. I'm beginning to suspect whether my window cleaning funds are being misappropriated for other purposes. Of course, my monthly contributions don't pay for a holiday in the Swiss Alps. But this is clearly not small-time embezzlement. I suspect a window cleaning racket. A national, underground network of "dutiful neighbours" who collect our window cleaning money and pool it so that each month, one of them can spend a week in a snazzy hotel and swipe some more stationery. I'm considering a major undercover investigation...