think about it , you have to cover your costs so hi integrety board £79 plus RCBO's say 2 £70 ,£149 , days labour £200 so £379.00 , but in this you have to cover you insurance , van running costs , trade body , mist things screws etc , notification charges , meter calibration , WAT on tools etc even spread ove the whole year your not left with huge profits on a board change .. unless you on rouge traders then it will be £1,100.49