Long story short I was cleaning some Velux windows on 3 newly built cottages. This Thomas Sanderson van pulls up with some blinds to fit. I thought I'd ask him about their conservatory valets. He said he didn't get involved in that side of the business but had heard that the most expensive was in the region of 3k . I asked him what they used to clean connys with, he said it's some chemical that they spray on and leave for a few hours. They go and clean inside while this chem is doing its magic. Then they go outside and clean off what the chem has dissolved. They're there all day he said. I'm not surprised at those prices I said. Then he goes to his van and gets a small glass jar out of the glove box. In this is dirty water, the top half has been treated with by a new chemical we have developed he said. He shook the dirty water around in the bottle and bugger me the dirty water just slid off the treated half of the bottle. Imagine if this potion was used on all new glass? Would it last long? I dunno, but there's food for thought!