Robotic voice left a message that my personal property is being monitored and it's important they hear from me before they proceed with legal matters. Clearly a scam.

Same as Scout's experience.  Wish they came up as something other than "No Caller ID" so I could block it.

A lot of call blockers allow you to block anonymous and no caller id calls.  You might want to check the documentation that came with it to see if you can, or go to the web site help area.