The building work that comes with a roof. One trade and one visit, rather than three trades and three waits.
What the roof actually sits on. A sagging line in a roof is rarely the tiles.
Rebuilt where they have rotted or been cut about by someone else's work.
A roof job that opens up and turns out to need carpentry does not become somebody else's booking and another fortnight.
Because he can do it. Most roofers stop at the tiles and hand you a second trade to chase.
Michael comes out, gets up there and tells you what it actually needs, in writing, for free. Usually within a day of you asking.