I only ever refused to work on one bike in my whole career as a bike mechanic too! It was owned by a local farmer who had always bought a new cheap bike from us every year and then just run it into the ground but this time he brought it back for an annual service. Except it was absolutely covered in whatever excrement he had lying round the farm, and I mean covered. It was inches thick in some spots! He agreed to wash it before we took it in so it went through the local jetwash then came back to us to give it a pretty much complete rebuild, returning it to full working order. Amazingly it was just new cables and plenty of regressing needed, the crap has been doing a very good job if acting as a natural rust sealant. When he returned to pick it up he was so grateful he gave us a crisp packet with some money in it as a tip, it contained nearly £300 in 20’s. It was when he passed away a few years later and his sister called in the shop that we found out they he’d placed a bet with her that his old bike could be brought back to life after she had berated him for wasting money in always buying a new one every year. The fact the repair cost and the tip was way more than the bike had cost new didn’t matter, he won the bet.
Mr Thomas, you were a living legend in that shop.