For instance, Proudspire's porch, after it has been upgraded. Or Honeyside's porch / dock (or garden for that matter) Or... So what's the process to find a cell ID after purchasing it's related upgrade? Is it a different process for 'exterior' locations? For instance, it looks to me that Proudspire's porch is actually part of SolitudeRow.

Yes, yes... I am THAT dumb.

I have not checked out the player houses to know exactly how Beth did it.

But, chances are that either:

• They have used upgraded cells and are switching doors (enable/disable) to get the player to the correct cell
  
• OR they are merely enabling/disabling objects in the same (not upgraded) cell ... which makes it look upgraded

There are quests associated with buying/improving houses, so you would need to take a look at those to try to figure out exactly what is going on

(unless someone else here has already figured it?? ... and they probably have as there are a good number of "player-house mods")

The cells remain the same and the upgrades are merely enabled in a timely manner via enabling of http://www.creationkit.com/Reference#Enable_Parent (usually XMarkers). Stuff inside or outside can be enabled via enable parentage regardless of the location of the parent ref. In the Creation Kit, you'll see the upgrade items have blue lines linked to their enable parents. That's probably about the easiest way to tell what controls any given home upgrade.

OK, looking at the link I think that I understand the principle. Run script, disable parents opposite-disable (enable) children. Am I on track so far?

But, looking at Proudspire's patio, it seems to reside in SolitudeRow exterior cell. I cannot find the enable parent tab for that cell, nor any references (obvious, anyway) in the actual clutter on the porch.

With one of the upgrade items that is outside:

R-Click > Edit > Enable Parent > View selected reference

That should invariably lead you right to the parent refs which are probably inside with the rest of the parent markers.

Thanks... I think. Now to see if I can utilize that info to make a porch befitting a Proudspire...