Is there a particular reason you built near the edge of your property? Let me guess this reason also extends onto their property? You should always make sure when choosing your site on a large parcel of land that your neighbour may build close to their edge, common sense, and adjust accordingly.
One of my properties I ended up selling, had over 50 acres, 2/3rds trees but we still carved right into the centre of it, through trees, so that it was unseen from every ground position. Slight elevation. Pretty good privacy.
