Your switchboard is older than your phone. Here is why that matters

A rewireable ceramic fuse protects the wiring. It does not protect you. An RCD cuts the circuit in about thirty milliseconds when current starts going somewhere it should not — through a person, usually. That is the difference between a fright and an ambulance. If your board still has porcelain fuses in it, that is the job worth doing before anything else on your list.