The Storage Summary Report can be found under Reports > Storage > Storage Summary.
Once selected it will bring you to the screen shown below:
RED - Here you can choose the Date Range you would like the Storage Summary to be for.
ORANGE - If your company has multiple branches you can select these in this Drop Down.
GREEN - If you would like a more Detailed Storage Summary you will want to check off the "Detailed" Checkbox.
YELLOW -Don't forget to click "View"!
PURPLE - These buttons will allow you to either Export to PDF or CSV file.