I've got a similar pressure sprayer, if you adjust the jet you can get a needle jet which has reached all the finials & detailing on conservatories without any problem.
For fascias, soffits and gutters I've got a long bristled flocked brush on the end of a harris pole - which I dip in a bucket of TFR solution and brush all round the guttering - it can also clean all round the brackets and up the back of the guttering. By the time I've pre-soaped up a lenngth of guttering it's time to swap to WFP, with old brush & needle jets, and give the area a quick brush over & rinse - job done
Dave