Your surveillance won't have the same weight in ct - basically I would think that your two choices are do it or not. I guess you could write down lic plate numbers and such that U see at the house. But, it won't be the same as having the officer there doing it - with the officer, they wait until they decide they have enough, and then go get a search warrant from a Judge.
U just have to decide if you wanna risk the guy finding out you allowed it on your property or not. In most cases, this should not even come out. But, if it were me, that would be my deciding factor. Does that risk outweigh your desire to stop the guy. Only U can answer that - Undoubtedly, U will get advice telling you to do it by other members here - but they don't have to live next to the guy. YOU do. You must decide what you want to do on your own. We both know the guy needs to be stopped - but what do U want to do?