preventative maintenance

Well the HV battery, brake actuator, combination meter will all eventually fail. So save up some money to repair those items when they fail. New parts will run you into the thousands (except combination meter)

 

Those items don't really need to be monitored. When they fail, you just replace with new. Don't waste your energy on stuff like that, it's not really in your control

 

Change the brake fluid.

Replace wiper blade inserts, if needed.

Check the pressure on the spare. Clean up while you’re in there.

Check the 12 volt battery with an electronic load tester, see where it’s at.

Raise the car (safely), say one end at a time, clean up suspension rust and apply rust proofing. Remove plastic panels for better access. Back out any small bolts/screws, oil soak them and reinstall.

Lube all door hinges, ditto for good and hatch, license plate bolts.

 

Fluid Film is highly regarded. Haven’t used it myself though.

I used boiled linseed oil (readily available in hardware stores and paint places) by the quart, applied with foam brush. It’s worked out well; even over existing rust, seals and stops it, quite durable. It was recommended by @tvpierce IIRC.

For small bolts, any thin oil Is good, say something like three-in-one.