A lot of real estate agents have 360 cameras.

or maybe have them on camera?

Responsible people have friends and family who will loan them money to get situated.Speaking of keys, I would install combination locks on the bedroom doors and unhidden security cameras in the hallways. 

Two bathroom faucets leaked.In stead of doing other things, I will secure of the place first, installing fences, lights and cameras.     

Seeking advice on what's the best and most cost effective camera in taking photos?

Are they full or will start from scratch leasing/sales.You need to get a diver or if the water is clean enough an underwater-vision camera and inspect piers and anchorages, if those don't hold in a flood or high tide you'll break loose and float off, nothing like watching a dock with a million+ dollars worth of yachts/boats crash into a bridge.....

I take their drivers license and info, and also have cameras on site to be able to monitor activity and let them know as much also.

The HVAC guy gave me a few options:1) Bare Bones $5000 - It will keep the place cool for roughly 8 years2) "Old Reliable" $7,500 - It cools, and is known for 15+ year life and a 10 year warranty3) Bells & Whistles $10,000 - High efficiency (we won't pay the electricity on this place), Variable speed comfort (it basically can adjust how much air it blows so that your house is at a constant temperature), can be connected with the "smart home" system so I can change the temperature or lock/unlock the door from my smartphone, have security cameras, connect the smoke detector etc.

Add a ring camera to monitor front of house. 

We have cameras but they ignore them.