When you have Rooms placed in your model it can difficult to see there extents without having to move your mouse around to find the cross that indicates the extent of the room. This cross is called the Room Reference.
In the Views Visibility Graphics under the Rooms Category you have the ability to turn on the Room References. They are turned off by default. This will allow you to see all of the Rooms that have been placed in your model without having to move around and find them.
If you also turn on the Interior Fill, your rooms will also be shaded blue.
Now you can check all of your rooms easily.
Just make sure you turn the sub-categories back off before you start printing.