Our Amazon has had at least two bouts of nasty bacterial infections in as many years so we’ve been taking the cage out and spraying it down with F10SC, or if going outside is not an option at least spraying it down fully with a mix of vinegar and water, as well as running toys/perches through the dish washer, monthly. I do daily wipe downs on everything (cage and playstands) with hot water to remove any visible poop or food particles and once a week soak dirty perches, toys and grates and do a more rigorous spot clean on the play stands.
I have a paper on the wall of my office where I write the date I last deep cleaned the cage, playstand, and small playstand, as well as when I’ve changed the humidifier and air filters (and when they are due).
His cage does have rust but only on the tray where the paper sits so he can’t access it, it only really bothers me! I don’t have a pressure washer though, I just use the hose and scrub with either no scratch dish pads or towels.