So why is residence a requirement for the janitor??
Even when we focus on the fiscal aspect of it, I don't think a machine is a bad idea compared to a plan of "find some willing to clean up after addicts and the mentally ill at all hours" - how much would you need to be paid to take that job and show up to outcompete the toilet-dishwasher-machine every day? California has tons of other jobs and generous social programs.
And that's ignoring the angle that we're allocating a human life to this extremely unpleasant and automatable task.
Yes, I clean my own toilets at home.