Managing Spaces and repeating Apartments/Units

[techdef 19]

Hey folks,

Our buildings tend to have a few repeating units throughout. Easy enough to either use Symbol or Reference to keep them separate and readily updated. The cherry on top would be to use Spaces to identify the units and do overall building Gross & Net area calcs. It seems for that to work right, you need to be able to select the exterior walls of the unit, which is not possible for reference or symbol? How are you guys doing it?

[techdef 19]

Aha, it seems to be possible if you use layer referencing rather than viewport referencing