Better protection is an arc-fault breaker, because arcing from missing insulation is one of the dangers of K&T.As for insulating, obviously anything that looks like it is loose or coming apart I would re-wrap with good quality electrical tape (electricity off, of course, when you do this) but beyond that you want to keep combustibles away from the wiring. 

What types of insurance do most investors make sure that they have to protect themselves and their properties against lawsuits / claims from tenants?

When you have more assets or a larger company, states like Delaware, Nevada, Wyoming may make sense if you are looking for charging order protection, anonymity, business friendly case law, etc. 

Sure it suffered due to COVID, but rents are already higher than they were pre pandemic. 

For me personally, in addition to the extra protection the LLC provides, there is a law that prevents us from having more than 10 conventional mortgages under our personal names. 

I believe our society would be better off if we stopped protecting people from the consequences of their own choices and actions. 

Given this risk I would be talking to a landlord tenant attorney ASAP to protect myself.

Everyone wants to pinch pennies - until something goes wrong.PMC's are like insurance, you don't pay it when things are going wrong, you pay it to protect you from problems.Is this a Class C building?

I'm part of the electorate whose lines are gerrymandered so as to protect the entrenched power and dilute my vote.

We set a time to arrive with the officer and have paperwork to serve the tenant; (everything you go over in front of the officer) Here in Texas they can do nothing other than observe but they do have to write a report for their department which is a great tool when you sue the tenant for damages or eviction.Good Luck keep records of every text, email at this point do not speak in person with the tenant unless you have protection and witness.