Hold on! What is 'old style PVC cable?' My house is '77 vintage and there is no way I'm changing the cabling. It looks good to me. So waiting for the canons to open up!
I have no cert and one with the Deeds would be good.
There are six circuits, up power (incl water tank), down power, cooker, up lights (goes into loft), down lights, garage feed.
Not selling yet. Live in owned by me semi built '75 3 beds. Hoping to de loft extension. Years ago I put in a armored cable feed to the garage via separate trip box indoors. An RCD main box had been installed before I moved in ('11). Should I get a full check on cabling and what should I expect...