Thanks for the tip. I should have researched this myself. As it turns out, power washing a deck is not recommended and the type of bleach to use is "oxygen" bleach not chlorine bleach.
As far as the vinyl & aluminum, well .... you just have to test your approach in an out of the way area.
P.S.- Don't ask me how I know but, it is possible to bend aluminum siding and break vinyl siding w/a powerwasher (that's one you probably didn't see coming).