I know how to repair, so I dumped all the crap (lemon seeds) from the spray arms and the chamber under the filter screen on the kitchen table for her. 

As for the "jumper," you might want to spray a little WD-40 on the water handle...not only will it make it a "memorable" experience trying to turn on the water but "memorable" when trying to grab the fence on the way back across.  

I had a situation where a cartridge went bad and as a result was spraying water laterally onto the floor and flooded an entire house.

That is like saying is it necessary to take a shower when you can simply just keep spraying yourself with axe body spray through the week ? 

If it's drywall dust or spray primer/sealer (most likely) it's not an issue.

I have come home and he has left spray paint all over my floor.

This mostly applies to tenting or spraying a house.

I was recently informed by neighbors that he took orange paint and lined off an area across the front of the lot with "kill zone" spray painted on top of the line.

It was paid for and scheduled pre covid but then shut down then the guy spray foam truck died and finally he sub contracted it to someone else and they did a great job!

I would have the tile professional sprayed and would change sink, medicine cabinet, window covering, and light fixture.