Go to Settings > Users > Add New User
Then in popup, you have options to enter users Name, Email, to which Properties (if you have multiple), Room Types, or even Room Numbers they will have access.
And most important there is the possibility to restrict every feature of the system to any user by selecting one of the options:
Hidden (user will not see anything about that feature in his dashboard)
View Only (user will just view without option to insert/modify/delete)
View & Insert (User can view and add new details but can not modify old details or delete existing)
With that you have full control under any of your users in your property and you do not have to worry about unpleasant situations that may happen if each user has same access level.