There is no logbook out there which can possibly contain all the columns you need for absolutely everything.
When you apply for a license or rating, and there are particular hours requirements which aren't explicit and clear in your logbook, there are two possibilities:
Firstly, you easily have the hours. For example, to apply for an IR, you must have 50 hours x-country PIC. If your total time is 500 hours, you can be pretty certain that you've met that requirement, and whether the exact x-country time is 300 or 400 hours no one really cares. (Remember that, according to JAR, x-country is pretty much anything outside the circuit.)
Secondly, you are very close to having or not having the necessary hours. In this case, there is nothing for it but to go through your logbook and add up the exact totals. If you are clever, you will do this in advance as you go: for example, my logbook does not have a column for ME PIC time. It has columns for ME time and for PIC time, but not for ME PIC. It was a requirement for me to become a ME instructor to have 30 hours ME PIC. So, at the bottom of every page, I made a note of the ME PIC time. Even if you don't have the foresight to do this, though, the hours requirements that are likely to fall into this category are generally small enough that you can go through your logbook and add up the totals reasonably quickly, certainly less than an hour, in most cases.
Do you use the 'Remarks' for that for example?
You certainly can do - doesn't really matter as long as you can get the number from somewhere.
FFF
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