Hi Dean,
If the window frames and sills are really bad we put a 'line' of Cif on the brush and try to give them a scrub.
These days we point out to the customer when quoting that the grey is built up dirty and seal stains and although we clean the frames, these really need to be restored by hand which will isn't included in the quote - most customers understand that. Anyone who thinks that we should clean the frames as white as when the windows were brand new are going to be a difficult, unhappy customer and IMHO probably best avoided.
Although we clean the door down and will clean hand grease marks off the door around the handle, cleaning off black boot marks on the bottom of the door or other impact marks isn't part of this clean.
We did the local school last year and gave the windows a first clean with a Virosol mix, but I think that the extra time and attention wasn't worth the effort when looking at the final results.
Spruce