It's tough to answer your questions without a more detailed description, Andrew, or some photos. If you get something awkward in future, it may help if you take a photo of it and post it up with your question.
For your first question, I think you're talking about soffit cleaning; the plastic area that the drain pipe is attached to, and there's a window preventing you from placing your ladder in the area that you need to get access to. Is this correct?
If so, a ladder stand-off (google for pictures) may help get access, but without seeing the job, it is difficult to advise. I would strongly advise that if you cannot do it safely (and if it doesn't feel safe, it probably isn't), then don't do it. Bouncing off someone's patio for a few quid isn't advisable.
And for your second question, are you talking about a conservatory roof clean?
There's various techniques you can use, and assuming you haven't got a WFP, you can either use conservatory roof ladders (which I've never used), or you can use a long pole that your applicator (your T bar scrubber) will fit onto and you could scrub the glass with that. And then using the same pole, attempt to squeegy off the soap and dirt. It takes a bit of practise, but you can achieve a passable result with this technique.
I hope that's been some help.
