How are you doing Z-Order?

Protip: Do so before, otherwise you are spending hours moving objects around.

I go from big to small. For example: Street -> House -> Floor - > Room - > (bed, desk, chair)

Here's a screenshot of what I have now.

z-order example

There's one's own shorthand. N means north, and so forth. There's a bunch of chicken scratch notes as I go about filling rooms. 

The nice thing about this is that I can shut off entire sections & floors. Working on Floor 1 today? Turn off visibility & lock all the other floors. It's fun to do all sorts of Doctor Strange-like things moving walls around, etc.