I would put up a camera to help figure out where the nails are coming from.

Ring doorbell or similar camera to check on who comes in and out, and smart thermostat so you can change the temp before guests arrive or when they leave.

Locks, thermostats, lights, cameras, home automation, supply delivery,  anything you can think of that will allow you to monitor your house and keep records of activity. 5.

I do have surveillance cameras on site. 

Set up camera's during showings and listen to what shoppers say

Maybe installing cameras helps as you know when they show up and go home. 

Furthermore, I will throw free highspeed internet, which I have lying around for my various security cameras (mainly for me so I can see if it snows or whatever).I manage it with my wife.

A wifi camera could work I suppose.

After another break in, I’m looking for up-to-date info regarding video surveillance during rehabs.

We've had really good bang for buck value with Zumper as far as ILS goes.We also bought a matterport camera and create a virtual tour of each available rental which creates a nice interactive way for prospective tenants to see a space and get an idea for its layout before touring.We use Appfolio for management software and it pushes the listings automatically out to any ILS who will listen which has been a huge help not having to list the same property on multiple sites.