@Amy2390 I can certainly understand how your neighbors were perturbed by this behavior. As you say, he wasn't doing anything categorically wrong by isolating himself to his car to drink, smoke, and take calls - from his viewpoint, it might have been an act of gallantry to spare you from these activities being conducted inside your home. But OK, materially I'm not sure if there's a difference between a guest getting drunk, smoking, and chattering in their car versus doing all the same things at a local pub when they return to the home. Either way, their behaviors are influenced by things they do while outside of your jurisdiction, so a rule about coming back home sloppy is pretty unworkable.
If this situation gave you safety concerns, you might consider offering your private room exclusively to female guests (hosts who share personal living space are allowed to select only same-gender guests). And there are tactics for standing your ground and moving quickly out of situations so someone can't corner you into an unwanted chatter. But unfortunately, there's no foolproof way to prevent someone with emotional issues or a drinking problem from booking your AIrbnb. The best you can do is leave off Instant Book and engage in as much dialogue as you need before accepting to make sure the guest has earned your confidence.