Most encouraged by the support. A bit more progress.
The ridge tiles along the roof apex were given some texture with Mr S 500.
The sticky out dormer was roofed with corrugated iron.
The metal work was primed with VMS metal prep and the whole building, front and back, was liberally coated with dilute PVA.
Everything primed with Stynylrez black. (the photos look grey but it really is black - camera won't photograph all over black!!)
I'm particularly pleased with how that smearing on of filler has created a nice texture for the render.
As always many thanks for your posts.