I personally have small units (2BR max) and target traveling medical professionals, graduate students, and digital nomads.

Definitely consider installing even fake security cameras, they will help to deter unwanted visitors.

Furnished Finder for sure, but also get on some of the travel nurse or digital nomad social media pages.

Pay to have a plumber camera the system to check for broken pipe as well. 

We have resources to answer inquiries, local people to do in person check in and more, dedicated cleaners, off duty police officers to handle noise complaints, and am hiring offshore resources to better monitor noise meters and cameras.

First question: I have outdoor security cameras with one facing the pool area.

We have rentals with all different returns, but I'll say we've been selling anything that makes a single digit return.  

I use a porch camera to verify who made made the booking is who checked in.

If you ask the tenants to assume the charge, they may also (this actually happened) take the security cameras when they leave ("but we paid for them"). 

The type of property we had there would be 8 digits if you find it in Southern California.