Also, once you get done with a rehab (new carpeting, paint, etc.) in a unit, do a walk through the unit with a video camera (phone) and date it.

Illegal activity can happen like it does in MF, but if you have cameras set up, it can help to discourage it. 

Document their actions with a small video as I'm at the property often and take this evidence to the police and/or city.You might try a game camera that uses a motion detector and infrared to catch the action.

Upgraded locks, lighting, fencing, security windows, camera systems.

Re pipes the entire house with pex because the last tenants purposely broke the plumbing after being evicted,  I put a brand new furnace and hot water tank in because the last tenants stole it after being evicted.They were supposed to get internet so the security cameras could be installed said it would be this week but lied.

You can even use a service like rent for automated lockbox access so they tour without you (have cameras).Good luck buddy!!!

The house we have has exterior Ring cameras at the front doorbell, side gate, and backyard over the pool. 

There were tiles handing from the ceiling, and security cameras hanging off of them.

For my VHR, I have no cameras there. 

Upgraded the house with All new appliances, smart home gadgets and cameras also designer backyard What was the outcome?