It's like having door locks, alarms, cameras, neighborhood watch, etc...

Aloha,Put up video cameras that can provide evidence of who is trespassing on your side.

I take 360 photos using the zInspector app and Ricoh Theta camera. 

I don't want to minimize the importance of the photos or videos, as they are extremely important alongside a well written property listing, but the technology you should have available (phone, camera, etc.) should be more than sufficient.

I was a professional photographer for 20 years, it might just be because you’re using a slow shutter speed your camera caught a light somewhere and it created a lot for trail due to a long exposure.

I would also put an addendum in their lease stating they're responsible for any costs you incur due to their trespassing (lawyer fees, judgement amounts, etc).Also, consider getting a camera that aims toward the parking lot so you can see if they're trespassing when accused (you could get a wi-fi enabled camera and put it in the apartment of a tenant who is not trespassing).Finally, I would tell the other landlord the things you're doing in an attempt to stop the trespassing from happening.

I put a cctv camera  on the meter to take a look at 3 and 4 am in the morning to see if it is running.  

Hey y'all Quick questionIf I put security cameras on my property, i.e. duplex is there a disclaimer that I should get signed by the tenants, or is it just too risky and should I just remove the cameras.Thanks n Semper Fi BP

Well, they have fake security cameras!

Maybe it would be cheaper to hire an escort with a video camera to do it for me?