theUtmost:
I
That said, we have now moved into a much newer house: built in 2003/2004.
It has zero network wiring in it. It has a concrete pad floor (so I can't go under it). It has an architecturally "fun" single span single pitch roof - with no cavity (so I can't go over it). It also has internal brick wall through the hallway (so I can't really go through it!). Wall lining removal would be my only option and she-who-must-be-obeyed says nope.
I have dealt with a couple of these types of buildings, a method often overlooked is to shallow trench conduit around the peremiter of the building (in gardens etc) and drop circuits off as required using outdoor rated cable, obviously conduit T to rise up a vertical conduit and a wall box to enter the building as an where required..
Cyril