The House Has Gone Bust!

The House Has Gone Bust! is a side quest that is automatically failed after killing Mr. House because it is not possible to leave to complete it.

Walkthrough
This quest appears after killing or disconnecting Mr. House in the control room. Before this quest is completed (or failed), it will be impossible to take the elevator to another floor from the penthouse. This is due to Victor being hostile. Since he controls the elevator until this point and it will be impossible to speak with him while hostile, this seems to be a fix by Obsidian to turn control of the elevator back to the player character. The other side effect is that the player character is locked into the penthouse and control room until they complete (or fail) this quest.

After starting this quest it will usually be immediately marked as failed. In rare cases, the quest will be marked as completed, granting 505 XP, or even 755. However, it is unknown if Mr. House himself causes this XP boost or if the quest itself does.