So you are saying that someone who has just killed their adoptive parents as well as the two children they have brought into the world, goes to the bathroom and washes their hands to make sure they are clean, then washes their clothes and then methodically shoots themselves twice because this is ritualistic of being a Paranoid Schizophrenic.
Welcome back SimonG!
It has to be more than her hands. SC would have to shower or bathe or seriously strip wash - no-one's blood/spatter or gun residue on her at all.
She then has to remove traces from shower/bath/sink.
Dispose of towels plus clothes (unless she carried out crimes dressed in just knickers and tights from bannisters) and gloves, as there were no prints on the 25 cartridges loaded.
She then puts on a clean nightgown but fails to put on fresh knickers - that jars - to kill herself.
As a model, someone keenly aware of appearances, wouldn't she have chosen to meet her maker in a special outfit and fully made up?
Time didn't matter, as she obviously did all of the above while the police were sitting outside.
Perhaps it was because she couldn't see in the dark, yet managed to get herself oh so clean...