This is the EM thing near Grimswind Ruins?
I just let others guide me through.
The key seems to be knowing the housing system well-enough to know its many possibilities, creativity, and persistence.
I didn't have all 3 in the right amounts so I mostly had to let others guide me through.
Remember that there's multiple destinations: The gargoyle to have a glimpse of the creepy goings-on in that household, the various paintings for more clues, and the message board to sign your name. (There's more I'm likely forgetting about.)
-Galen's player