I know a thief or a liar when I see one.

Smoke alarms, CO alarms4.

I'm just curious to know if it raised any alarm bells for people.

It’s also prudent to review and update your properties' safety measures, such as installing fire alarms and security systems, as these can sometimes help reduce insurance costs.

It's a great idea in theory, but to be honest with you, this statement - "Getting a bit tired of my current job (first out of college)" is a bit alarming.

Tenant not paying is thief in my book any day.  

The driveway is 'Y' shaped, very narrow from the street to the back, then both houses have their own parking area in the back.The issue he is having is the other homeowner is 'accidentally' leaving nails, screws, and other puncture problem items on the driveway with alarming regularity.

TimBuilders risk policies will less likely to  exclude theft but might require an alarm.  

He also removed a whole house alarm system without telling me.

If it is is a group home, chances are you are going to need a commercial sprinkler system and fire control devices(pull alarms) and panel installed.