I have recently lost a couple of Hip Tiles and Ridge Tiles in the storms from my slate roof although the roof is old and many of the tiles are brittle i cannot afford the cost of a new roof. so i am looking at replacing the Ridge and hip tiles for now, how will the roofer replace the Ridge and Hip Tiles without damaging any of my existing slates i understand they can use a crawler ladder for the ridge but what will they use to gain access to replace the Hip Tiles and should i be asking any particular questions to the roofers that i am asking to quote for the work 