Even if you could get away with it without the police being called, it is extremely inconsiderate of others. 

Is a Signed Rental Agreement enough to go to the police station to check?

The city of Detroit has launched the green light initiative which streams live video directly to the police stations for areas that were war zones.

Originally posted by @Deanna McCormick:Month to Month,, tag and tow unauthorized cars on the property..Deanna, while I typically agree with your posts, the one above I find not practical to a certain degree, plus it portrays a "policing" attitude.

If some descendant from a previous owner finds he has inherited a portion of your property through a faulty Chain of Title then you will have to adjudicate a settlement that may cost much more than Title Insurance --- a one time fee.If you had Title Insurance in the example above then the Insurance Company would cover your expenses to recover in court or compensate you for the money you paid to buy the property. 

(as the renter may be under duress to allow it, afraid of the peddlers, and will not want the police involved due to retribution).Do you just fail to notice this and collect the rent; or try to counsel them or (???) 

And the police would only go in there if they were called in for an emergency.  

I called the police right away.

My perfect neighborhood will have a police car in one of the driveways.

Under the Good Neighbor Next Door (for teachers, police, firefighters, and EMTs) program from HUD, you take on a second "silent" mortgage for the 50% discount off the appraised value, and must OO for 3 years to receive the full discount.