Hi Dave,
We were asked to clean this place about 4 months ago, gave a price for it all, including the windows over the Tates flat roof, happy with the idea until we had a better site inspection and realised that the tates flat roof was not flat, and the windows were recessed behind storm screens.
We decided that it wasn't going to be easy to write a good risk assesment so declined the job.
The section you are doing looks fairly straightforward apart from the fact that you have very little foot room at the base of the tower. How are you going to access the balconies?
As you know Dave this part of St.Ives really catches the breeze! So watch out.
I would charge for this section about £40-55 depending on how bad you want the work.
Here is another picture of the tricky side!
Alex