I see a lot of bias when it comes down to whom is hired by whom in this situation. Is it the realtors sparky?, the buyers?
I see NFPA 73 used to define the 'line' , not by NEC, but fire AHJ's.
This is for big no-no's
-no receptacles in a room
-no cover plates
-extension cords under carpets
-open JB's or no KO seals
-loose or unsecured wiring
(basically the photo violations section)
So the next obvious Q is how to prioritize repairs, etc. when asked to comment on older maintenace-challenged dwellings over and above this.
-proper GEC & bonding
-proper Service size ( really no sense in growing branches if the trunks rotted!)
-Dedicated circuits ( kit, bath , etc)
-Possible AFCI's to those K&T circuits
-Split up & derate older circuits above
- reterminate & pigtail all old to new devices
-replace old & worn fixtures
-Home runs as far as possible, any future renovation to continue the circuit.
This is very generic, so don't flame it apart! I tell customers that this is how i would proceed if i were to move in!