The fronts remedial work I believe ree, im shocked you hadnt noticed! Make your own mind up about the back! new bricks have been fitted on the chimney and re pointed. Could that be the cause of the effloresence? We already have a noseall on this forum . Who is generally 99% correct with what he says. We dont need another ie (you) which ripped the roof apart all the way down to the roof line. A simple repair could pretty much cost 4 grand on your advice!