Converting UK house to RCD cost? What would it cost roughly to convert the old fuse style box...

What would it cost roughly to convert the old fuse style box to RCD for a UK house? a variety of prices would be nice.
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Answers:    Depends on many things. # of circuits, amps needed, etc. Maybe 350 - 800 pounds.
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You do not positively need to devolution your fuse arrangement to get RCD protection. One could simply install an RCD switch between your meter and the consumer element (with the fuses). That means that your electric supply would jump through the RCD first. That should cost, well, unquestionably under 200 pounds.