Cameras are a great deterrent and will help you catch someone if they try something.I would be concerned about safety of my tenants and liability when I rent that home to someone else.

Also go through the property inside and out and see what you can do to make it safer and less likely to be a trip/fall hazard.

I'm afraid to hazard a guess at the renovation budget.

I have talked with Building and Safety already to see about permits.  

And don’t worry about the flares, they are a safety mechanism.

Would anyone recommend keeping my personal umbrella as another layer of safety?

Housing can also inspect the unit for health hazards like cockroaches, marijuana, etc.Personally, I would tell Housing that you want these tenants out because they are destroying your home.

Good to know, since not being an expert on cars, I'd expect some type of hazard to come up during the actual work.

So of course I kicked them out of the house.Now, the electrician called me and said he wants me to call the city to check all his works just in case if I hired someone else to finish it and fire hazard happens, I will blame him for causing it.

Usually it revolves around life-safety features like smoke detectors, egress, etc, but depending on the locale can include that it’s reasonably clean, no broken windows, etc.