You pass through the door and find a room full of tools, assorted lumber, electrical wire and plumbing parts.
The majority of the room is roped off with a sign saying "Authorized Personnel Only"
There is a chair and table with a book on it in the section you can access though.
You glance at the book, which is open to the first page, what appears to be an index of some kind.
"Herein are snippits of our adventures renovating an approximately hundred year old building to house a clown school."
As of this moment only one category seems to exist.