Guides to running AI privately in an office

Offices arrive with the same four questions. Is a model that runs inside my own building actually good enough for this work. What does it cost. What happens to a file the moment it is connected to one of these things. And what am I supposed to tell my clients about it.

These guides are the long answers, written from the work rather than from a keyword list. Each one is dated, and where a guide cites a number that moves, it says when the number was last checked.