I have two large dogs that are on a tether when they're outside because my yard it's fully fenced. My neighbor lets his two Chihuahuas freely run around the neighborhood I've seen them multiple times in my back yard, but never when my dogs have been outside. My dogs have never hurt another dog, but they play rough with small dogs because of their size. I'm very careful with my dogs but I can't supervise them 100% of the time and I don't feel like I need to as long as they're well within the boundaries of my property. I can not complete the fence because I am renting the house. I try to be a responsible dog owner, I'm just afraid someone else's lack of responsibility could be placed on me. He refuses to keep them in his own yard.