If you are running in a multi-location mode you will see a small filter on your BRM
The default view is 'ALL' which means show data across all locations. (reservations and inventory)
However, if you enable the filter then you will be able to restrict the data to a given location.
here I have chosen the 'HYAT' location which has the following effects across BRM:
When creating a reservation I only see items with a Home Location of HYAT
When searching for reservations I only see reservations with a start or end location involving HYAT
When searching for inventory I only see Items with a Home location of HYAT
The behaviour of your inventory shape page depends on which mode (of multi-location) you are operating in.