A basic warehouse set over four levels.
Ground level with office/welfare facilities and a strong room (with a precious package) at one end, loading/unloading bay at t'other. Lots of shelf space for those packages of ????
Upper level with office/workshop (has been expanded now).
A little sewer entrance for the sneaky ones out there, and a skylight on the roof for the intrepid climbers. But maybe the occupants of the building have already covered these points of entry with some surprises of their own?
Have added a hidden sub-basement below strong room for data storage? (Concealed hatch is outside strong room). Maybe the current occupants don't even know it is there?
Rough scale of 1 sq=1m