The House Has Gone Bust!

 is a quest in Fallout: New Vegas that is triggered after killing Mr. House.

This quest appears after killing Mr. House. Before this quest is completed (or failed) you will not be able to take the elevator to another floor from the penthouse. This is due to Victor being hostile towards you. Since Victor controls the elevator until this point and you will be unable to speak with him while hostile, this seems to be a fix by Bethesda to turn control of the elevator back to the player. The other side effect is that you are locked into the penthouse and control room until you complete (or fail) this quest.

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