Think this out a little! You know who the guy is, or at least what he looks like! Install some security stuff that will allow you to monitor from a distance. Put some silent alarm equiptment in place that would be connected to the law enforcement.
Don't know how far you live from the premises, but it should be easy beans to catch someone that keeps coming back!
Maybe hold a wellm advertised public function there and have a street clothes cop there to grab him when he shows. You know what he looks like but he obviously doesn't realize it yet! Work that to your advantage!

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