The inventory location restriction idea is the same suggestion we have here
Hide Location from Restricted user, it is already in the ideas category.
But I also believe in restricting/hiding divisions from restricted users. But that wouldn’t mean the users wouldn’t be able to see the transactions of other users.
There have been talks on the introduction of ownership over transactions where users could be limited to seeing only the transactions they have generated (Limited action, "Create" only for sales man - #3 by lubos).
You can read more on that here (Search results for 'ownership concept' - Manager Forum)