Wasn't made aware of the £50 call out charge. However he did thoroughly check loft for leaking pipes, lifted up installation to check, but in the end it turned out to be some sort of fungi/moss due to water patch, that he just wiped off the ceiling at the end of his c20min inspection - and i thought it could be something major! It did pass my thought that perhaps this is something someone in the trade would have spotted instantly - then again, may its not so simple, hence i'm neutral.