Where should the main shutoff go, and how should it be labeled?

I’m trying to make a practical shutoff plan rather than assuming there’s one obvious valve. The key trade-off seems to be keeping the main shutoff immediately accessible during a leak while protecting it from accidental operation, especially if it’s in a utility area, crawlspace, garage, or outside near the water-entry point.

For a reliable setup, I’d want to record:

- Where the service line enters the house
- Whether the main valve is indoors or outdoors
- What type of valve it is, such as a ball valve or older gate valve
- Whether it can be reached without moving stored items or using tools
- Which fixtures have accessible local shutoffs, and whether those valves actually turn

A single main shutoff is simpler to label and test, but separate fixture or branch shutoffs could limit damage if the main valve is difficult to reach. On the other hand, too many labels or valves in different locations could slow someone down during an emergency.

What labeling system and access arrangement have you found clearest: one prominently marked main valve, a protected but unobstructed enclosure, or a combination of the main shutoff plus labeled local valves?