Well, there's Harper, of course. Whether you want her or not.
On the shelves to the right of the door, you'll find an odd note about "Charlotte's cryptic obsession with Jackson." I never discovered any relevance to this note.
To the left of the shelves you'll find a wine rack with some colored tiles; you'll need them after you get into Charlotte's bedroom.
Next is a stack of barrels, which for now is just a stack of barrels. Next to the barrels in the corner is a large machine that will turn out later to be a generator.
Next to the generator is a tunnel with a locked door at the end.
The Tunnel with the Locked Door
Finally, to Harper's left, there's a disassembled mine car. It's irrelevant until you get to the endgame.