Driving without a license on private property

I manage a rental community that is private property. It seems that a driver's liscense is not required to drive on our streets. It is only illegal if they speed, run stop sign, drive recklessly or cause accident. Why can't tickets be issued even if requested by management?

I'm guessing because there's no cop sitting there to write out a ticket?

My dad tells me that if you run a stop sign in a parking lot you wont get a ticket. It might vary from place to place. I'm sure if running the stop sign caused a collision, something would happen though. It probley depends on the situation I guess.

 
If they don't live there you could always get a 'trespass' restriction against them.