Plumbers, don't you just love 'em.
We have a rental flat, with another above. Tenant told us that there was water dripping from kitchen ceiling - so I go upstairs and inform the owner, he says he'll call out his plumber. His plumber says there's no leak he can find.
Water still dripping from our ceiling, so go and see chap upstairs who lets me have a look - a few seconds later I've found the leak (from the cold water connection to the WC ballcock). OK, it wasn't an obvious leak, as in visibly dripping, as the water was running down the pipe and disappearing into the boxed off bit hiding all the pipes. So leave him to call his useless plumber out again to fix it. But, the delays have meant that our kitchen ceiling is now sagging.
Roll forward a bit, chap upstairs rings me (while I'm on holiday elsewhere in the country) asking if I know where his stop tap is - which as it happens I did from when I'd been looking into the previous leak. No idea if I could blame his plumber, but the chap was watching TV when he heard a bang and water was gushing out from under his kitchen units. Turned out one of the flexibles to the taps had failed - no idea if it was pipe failure or not connected properly. So that's the end of half of our kitchen ceiling which we pull down so it doesn't fall down when it feels like it.
So when the tenant moves out (moving onwards and upwards) we get the kitchen ceiling replaced, as well as applying multiple coats of paint to cover the water marks in other rooms.
Roll forward a couple of months, water dripping from ceiling again. Chap upstairs gets his plumber out - who can't find a leak. Plumber asks me if he can make a hole in our bathroom ceiling (where the bulk of the water is coming through this time) and I agree a small hole "say, an inch or so" for him to put a camera through.
So, what do I find when the tenant tells me the water hasn't stopped ? He's left the fan dangling on it's cable, partially dismantled the ducting, and cut a hole about a foot square in the ceiling and left it. The **** told me that the water wasn't coming from upstairs, it was coming in through the fan ducting - despite the fan ducting being dry, and the concrete blocks ABOVE it being wet. Yes, a plumber who believes in water flowing uphill on it's own.
Upstairs to see the neighbour again - we do actually get on alright. For some unrelated reason he has the bath panel off, and with a torch and mirror I can see up the box and see a pipe going drip ... drip ... drip.
So that's the new kitchen ceiling with water marks, a gaping hole in the bathroom ceiling, and water marks across the living room ceiling.
I sometimes get asked if I know a tradesman for something or other. As I tend to do most work myself I don't really know what any of the locals are like - apart from the handful of plumbers I wouldn't trust to change a tap washer without supervision.