So, none of the four actually needed any serious electrical rewiring or complete rewiring for that matter. The picture opposite with the red and black cables are the most dangerous as the insulation had started to break down due to age and the rubber based compound it was made from. Be on your guard that other electricians may try and talk you into having a complete house rewire in order to line their own pockets, when in fact, all you may need is a partial electrical rewire.