@Delphi @ceilidhman This was only because the agent sent an electrician to have a look and he left in hysterics, begging us not to double plug ANYTHING.
When the rewiring was done and we had a crew crawling about under floors there would be bursts of hysterical laughter and a head would pop up out of a hole. Gesturing wildly to his colleagues to come and have a look. Further outbursts would follow. Apparently it was original Victorian DC wiring and 1950s/70s DIY AC wiring all jobbed together.