How to identify if the space is available in a particular location ?

Hi,

  In ARSB(Aisle, rack, shelf, bin) architecture for warehouse locations, suppose i have a location where in i have kept an item. For example: A Pencil box. So now if there is space available to keep more pencil boxes in that location, how can system recognize it ? 

In simple my question is "How can we identify how much space is filled in a location and how much space is available ?" And in case the space is available then will the system suggest me for available place in a location so that we can place next item in same location ? How to configure this ? 

Thanks in advance !!