I can't even stop my family that lives with me from overloading crappy extension cords; most people, including my tenants, don't know enough to avoid overloading extension cords. Frankly, all extension cords with a NEMA 5-15 or 1-15 plug should be required to either be rated for 20A, or include over-current protection; and the fuses should be shaped to prevent you from putting an over-current fuse in the fuse holder. But alas it doesn't work that way in the US. (It does in some countries).
That said, I drive by all my properties periodically, and my property manager does annual walk through; large battery banks, excessive extension cords tacked to the walls, and solar panels sitting on the roof with wires run through a window would all get flagged in such a walkthrough, any my rental agreements allow me to require the tenant to correct unsafe conditions, which all of those are.
And I do have good insurance. There's a pervasive believe on HN that you can't get insurance that covers variations of not-to-code, not-properly-permitted, and/or not-done-by-licensed-electrician electrical installations. There very may well be insurance that excludes these things, but its easy to get insurance that covers those things, and mine does. If my tenants do dumb-ass stuff that burns the building down, I'm covered, even if that dumb-ass stuff involves electricity.
How does one stop tenants using "dodgy" chargers to charge their electric bike or whatever, and the battery bank causes a fire.?
Does your insurance cover these situations???