Screens come clean with soap, not force
The mesh is cleaned chemically and rinsed at low pressure. Hit it with a wand and it either tears or pops the spline, and re-screening a cage costs many times what the wash did.
The frame is where the black streaks live
Mildew sits on the top of the horizontals and in the corners. It gets treated and given time, then rinsed from both sides so the run-off does not just move it onto the deck.
The deck at the same time
The lanai deck is usually the point of the whole job. It gets a surface cleaner where it is concrete and a gentler approach where it is pavers or coping.
Tell us about the surfaces. Somebody will come and look at them.
The chat takes the surfaces and the address, then hands it to the desk. It books quotes — it never prices a job in a chat window.