When using this system, do I have to put just one piece of paper per hanging file folder? That seems very inefficient and would take up a lot of folders/file cabinets. I like to keep like things together (i.e. everything about the "ABC Company" in one place).
No, you do not have to put just one piece of paper per hanging folder. You can group as many files relative to one another as you want. Just be sure to input keywords relative to each item that you put in the same hanging folder.