When you're at traditions of the trade, enter the double door behind the reception, into the dark hallways. There's a room nearby where a security guard is taking a bath. If you're fast enough, you'll notice a ghost looking at you when you reach the room. Then the ghost enters the room and scares the security guard who is in the bathroom (meanwhile you can get his suit). The same ghost can be seen in the room where a dead body lies (walk a little further, and you'll see a guard in front of it), if you look at the bathroom's mirror carefully (you'll see its reflection behind you, but when you turn it won't be there). If you look carefully at it, you'll see that it's the man that was murdered in that room.