This would be a great feature! I'm getting more bids with areas broken down into sub areas where they'd like a total for the sub-areas as well as for the overall area.

I agree! I recently had a client request that each room be separated out, and then each system (networking, audio, video, control, lighting, wiring) be separated per room. I created over 220 areas, since they required we separate them out. This would be super helpful.

Yes, Sub Areas would be very nice. Please add this!