I don't think you're overreacting. And I agree heartily with your commenter who suggests you introduce the people who will be staying at your house to your neighbor — and if you still have a bad gut after that, get in touch with your local police to let them know about your houseguests and even your reservations about your neighbor. Do what you can to protect your friends and loved ones in advance. And then, yes: hope your suspicions about your hog-riding neighbor are wrong.