On the roof
Walked where it is safe to walk, measured properly, layers counted at an edge or a vent.

One number, answered by somebody who has been on a roof this week. Say roughly how old the covering is, how many storeys, and whether a skip could stand anywhere on the property.
There is no form on this site, deliberately. Three questions about access and age settle in two minutes on the phone what four emails would not, and the emails end in a call anyway.
7:00am – 7:00pm
7:00am – 7:00pm
7:00am – 7:00pm
7:00am – 7:00pm
7:00am – 7:00pm
8:00am – 4:00pm
Closed
Walked where it is safe to walk, measured properly, layers counted at an edge or a vent.
Where there is attic access, a look at the sheathing from below for the staining that tells you how long something has been wet.
Where a skip stands, where the ladders foot, and what has to be boarded over. This is what decides the timetable.
Itemised and handed over at no charge, specific enough to hold another quote up against.
An hour on it and under it, then an itemised sheet you keep either way.