"Those" Neighbors

Have you ever had those neighbors that no matter how good your yard looked, theirs was always going to make it look bad? We have next door neighbors that we just don't know what to do about anymore. First, it was their 4 dogs that barked incessantly to the point that we couldn't even hear our TV. Then, it was their cats that decided our back porch furniture was more comfortable than their own and they left most of their cat hair when they left. Now, they just don't mow the lawn or prune their flower beds (if you can call them that). It has become a real nuisance in our neighborhood. I could understand if we lived in a run down neighborhood, but we don't. I could understand if the family was going through a rough patch, but they aren't. (Trust me...private schools for their 5 children, nice car, etc.) I think the biggest problem I have is that they have two teenage sons that could easily take on this task, but they don't (or maybe aren't even taught to do that). Just irks me!! Any suggestions on how to remedy this issue?