I am setting up a shared document to which 27 different users need access.
Each user will have their own tab which they can edit. I would like to
restrict what each user can see. The content is not top-secret so it doesn't
matter if it's easy to crack.
In an ideal situation I'd like that when the user opens the file that it
asks for a password. The password would open access to whatever tab the
password applied to. There would have to be an overall password which allows
visibility to all.
I'd prefer if users could only see their own sheet.
If it makes a difference the 27 users are accessing from fixed sites in a
network so the file could restrict access based on network location. (The
admin would access from anywhere).

Can this be done? I'd like to set up a template for this can be be used for
different purposes. any ideas are welcome.

Thanks