Where is the Hufflepuff common room in Lego Harry Potter 1-4?

You won't find the Hufflepuff common room in Lego Harry Potter 1-4. The game only includes the common rooms for:

* Gryffindor: Found in Gryffindor Tower.

* Slytherin: Found in the dungeons of Hogwarts.

* Ravenclaw: Found high up in the towers of Hogwarts.

The Hufflepuff common room wasn't included in the game, likely due to limited space or a focus on the most popular houses.