Fascia and soffit cleaning
Green algae streaks and general grime on fascia and soffit boards are mostly cosmetic, but they are also often the first visible sign that gutters upstream have been overflowing.
Usually a add-on, not a separate visit
Because the vacuum pole is already reaching the roofline for the gutter clean, washing down the fascias and soffits at the same time is a small add-on rather than a separate call-out.
What it will not fix
If the boards themselves are swollen, cracked or starting to detach, that is a joinery repair rather than a clean. Richard will point this out rather than wash over a problem that needs replacing.