At this point, I would be less concerned about the age difference between J and S, and more concerned about S's attitude toward guns and apparent lack of understanding of property laws. Does your cell phone have a camera? Every time you catch him on your property, or see evidence of his presence (like the paintball stuff) take a picture. Keep a file. Contact the police every time you see him on your property; then they have to keep a file as well. When you eventually have a face off with him (and I can't imagine you won't) you will have a record of his behavior - he trespasses on your property, he vandalizes your property, and he's been reported to point guns at people and use them on others' property. Warn him off every time you see him or signs he's been there, and document the warnings as well. Then when you have to throw him out bodily, you'll have a body of evidence (both your own file and the police file) of the number of times and ways you attempted to get rid of him some other way.