How will you look for it?
When you need to get to the details of meetings what do you think of first? "I need to find the meeting notes." or "I need the notes on Group A and it was a meeting."
Personally I have 1 large A-Z system. Within is one grouping like you mentioned Equip. - Item where item is the particular thing. That's where I keep manuals, warranty info and anything else related to physical things we own. I have 3 entirely separate filing systems for 3 distinct filing needs. One each in A-Z format for files related to the 2 organizations where I am a board member and one for my genealogical files because they follow a very specific format by surname.
The problem with categorizing things by AOF is what happens when a file crosses boundaries? It may not happen to you much but it sure does to me. I quickly lost track of stuff when I had multiple files like that.
Oogie McGuire - Mac, iPhone & Omnifocus
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Paonia, CO USA