When water's going everywhere in your house at 3am, it's difficult to work out what the feck to do.
We had a leak in the kicthen a few weeks ago, it turned out all it was is the compression joint on the stop valve for the washing machine supply had gone. It took me and my dad (both DIY idiots) half an hour to replace the valve. A plumber would have charged £100 for this.
I guess if people have money to burn then thats their business. The only time we have used a plumber in the last ten years was when he wanted our gas fire disconnected. We decided to live to a corgi registered person because of the dangers involved.