Awhile back I had asked where I might have a water shutoff on my
property. Looking at the hints, the only one I can find is the
municipal one undera manhole cover just off of my property. Of course,
the city doesn't want me to play with it. The only way for me to do
some plumbing improvements is to have the city shut it off, and have
them turn it on a few hours later--and hope everything is OK.

I don't like this idea and was thinking about the work required to
install a shutoff. It sounds like a PITA that isn't cheap to do.
Recently, I had thought about the work that goes into installing a water
softener, and I wonder if I could exploit that to add a shutoff. I
assume I could keep a water main shutoff inside the garage this way,
next to a water softener. It seems like the most convenient way to go
about it, but I wondered if there are some perils in doing this.