If you alter your car its electrical harnas wiring and this creates a short somewhere, resulting in your car burning down ... that is a whole difference situation then missing a mandatory inspection. One is deliberate alteration of a vehicle and one is a inspection of condition.

Most insurances have a lot of protective language (for the insurance company), that often comes down to "everything needs to be code compliant/manufacture original/...".

The bigger the damage, the bigger the chance that insurance companies will fight you. If the above mentioned installation creates a small kitchen fire that cost a few 1000 bucks, they probably are not going to fight it.

But what happens if the above mentioned installation burns down the building, kills 5 people... Do not forget that the other neighbors / building owner's insurance companies, will go after your insurance if you are identified as the cause.

The issue is that if you go to court, and a fire comes from your apartment is from a accident, or a state like this, courts are willing to side with the victim party. But if a fire is the result of your own "tampering" with devices, electrical, etc, there is a very, VERY high chance that the court will side with the insurance provider. Insurances are not blank "do whatever you want, you get coverage" type of deals.