Since a cloud can go offline to outright vanish, only the very new IT would "store" their last copy of such things there.
Also, you have quite a list of requirements for a free service. If you must do this why not a small file server at the office? That's as free as it gets.
We're looking for a cloud storage software where we can store key company documents in a centralized place where employees can access them.
We will have around 50 users and would rather not pay a license per user. We also need to have controls over which users can view and edit documents.
Does anyone have recommendations? Thanks

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