install GS two times under /ClientOne and /ClientTwo directories, and your clinets will be able to manage all of theirs pages content independently.
Otherwise search for multi user plugin, although I have no idea if you will be able to assign an user ability to edit certain page or at least menu tree.
Otherwise search for multi user plugin, although I have no idea if you will be able to assign an user ability to edit certain page or at least menu tree.
Addons: blue business theme, Online Visitors, Notepad