...an after-hours shutdown to replace a faulty gate valve at work. We do commercial office renovations, and it seems like any time we need to tap into a domestic water line, we find out it can't be shut off, either because the isolation valve has stuck open, or there was never an isolation valve installed in the first place. I've come to realize that commercial developers are some of the most short-sighted, bean-counting people ever. Of course, I'm sure their angle is usually to "build it and then sell it", so dealing with maintenance issues down the road isn't really of any concern to them. That mindset sure makes life difficult for everyone in the future, though.