Speculating as usual.
I have ladders but cleaning a semi-circular bay window is a bit precarious and involves a lot of moving of ladder.
I also have a caravan which would benefit from a roof clean every 6 months or so.
Hiring a platform looks to be around £100 a go. Buying one around £1,000.
I've just seen an advert fro a "platform tripod ladder" which is mainly aimed at cutting very tall hedges but it does get you up there on a more stable platform than a leaning ladder.
These seem to come in at around £300 for 3 metres plus, but cheapest may not always be best.
Upstairs window cill is about 3.7 metres off the ground.
Anyone got one of these tripod ladder thingies?
The main potential down side is having to work sideways on but I don't think that is a major issue.
Cheers
Dave R