TL;DR: How careful do I need to be in opening and closing the main water valve at the meter?
My end goal is just to change out a shower cartridge and there’s enough great videos on it that I feel comfortable about that task. It is a positemp cartridge and I wish I could just rotate it slightly as my showerhead is just leaking from the hot line. For some reason, there are no stops in my shower’s valvebody (picutre included just for reference).
It is a two story house with each level having its own ground floor and, for various reasons, I do not have easy access to my house’s main water shutoff or the upper level, so I plan to shut off water at the meter.
Here are my questions:
I do not know 100% sure if the box I have located is solely mine or my neighbor’s. Is it common to keep two different property’s meters in the same box? The arrows make me think they are not my neighbor’s, but what gives me pause is I don’t see where their box would be located by the curb.
I suspect the second meter (top) is for irrigation and drives the sprinklers. Do I need to shut it off as well?
Once I get the water closed off, I know to drain the hot and cold lines by opening faucets in the house. However, can I avoid doing so for the upper level and drain from the lower level? I don’t know if it matters, but the shower repair is in the bottom level. If I must drain the top, can I get away with opening 1 faucet?
When I turn back on the water, I also know I should do it slowly and to preferably have valves open. Again, is it enough to have the lower level running? If not, can I get away from water hammer by having only one faucet running on the top level?
Thank you very much for any help.