I spent thirty years telling people what their houses were worth. Last month I found out I had my own wrong by about ninety thousand dollars.

You have already read the paperwork. That was never the hard part.

The words are not difficult. They are arranged badly, on purpose, and most people who subscribe here have gone through them once with a highlighter already.

What reading cannot give you is the other end of it — which line gets checked first, what is calculated and what is somebody's judgment call. I worked on that end for thirty years, which is useful, and it did not stop me from getting my own dwelling limit wrong for six years running. That is roughly the balance of this letter: half what I know, half what I keep not doing about it.

Most money writing is about something you might do next: buy this, move that, get ready for the thing that may or may not happen. Which means the writer has to be right about the future, and you cannot check any of it today.

I write about paper you have already signed. It is duller and it is a good deal more useful.

Nobody covers this because you cannot sell a subscription on fine print, which is exactly why it is still worth reading.

You keep the family's papers. Thirty years of paying the bills, watching the renewals, keeping the folder. Organised, and without illusions. Your question is not what does this mean. It is where could I be worked around.

You run the money yourself. You read primary sources and check the footnotes. You know more than most of the agents you have spoken to. You are here for the order things get decided in.

You already got a number. Fire, water, roof, wind. You learned the process thoroughly while it was happening and still do not know why the figure was what it was. That question is most of what this letter is about.