Trumpy,
A smart DIY-er should know when a job is beyond his capabilities and when it is appropriate to call in the (duly licenced)professional.
For instance, while I'm not afraid of replacing rotten cable inside walls and adding new sockets (as long as it's within circuit capacity), replacing cracked wall sockets, or broken switches, I will not try to undo the hack-job pictured above. Nor would I try to completly wire up a new house without help from a pro.
An even more morbid example. My aunt's apartment building in New York has rotten wires in the walls, coupled with a by-passed fuse box (no protection), surface-mount zip-cord (plug one end of the cord into an outlet and staple it along the wall) extension sockets, rusting boxes, etc.
Her landlord is a slumlord who has refused to fix this crap up.
I found out how bad the wiring was when replacing a worn-out, ancient wall socket (the plug pins literally slipped out of the holes) took about a day's work trying not to further crumble the perished insulation and not letting the box (which had come loose from the studs) fall into the void behind the plaster & lath!!
The building as it is is a firetrap, the owner refuses to fix it...and if I start poking around in that hell I'll probably be responsible for more bad than good.
