Who Let the Dogs Out

As I've mentioned, we a fortunate to live on a small cove that is part of a larger lake.  The lake is a big all-sports lake, but our cove is small and cozy.  The lots are tiny and most of the house are remodeled cabins.  Everyone knows everyone else and, all in all, it is a really nice place to live.
So, as it happens in life, our neighbor passed away a few years ago and her house has been empty since that time.  And, because, let's face it....this is pretty much all about us all the time,  we've spent that time worrying about what will happen to the house.  Because, like I said, things are close around here.  It's kind of like living in a dorm, but with water in front of you.
Anyway, this past summer our neighbor's daughter decided to move back with her boyfriend and their three--yes count them--three dogs.
Now, don't get me wrong.  I like dogs.  I have a dog.  But I like dogs who are well-cared for and whose owners have a healthy respect for their dog's place in the world.  And I knew I wasn't going to find that here when I met Mr. Boyfriend and he proudly announced that one of the dogs was a pit bull that he used to fight. 
What the hell?  Who does stuff like that?  And who feels that this is something that you proudly announce to neighbors that your just met? 
Of course, this sets me into overdrive.  I call animal control and they tell me that they really can't do anything based on something that someone told me.  They need physical proof that the dog is being mistreated. 
That's where we are right now.  As I talk more to Mr. Boyfriend (and yes I am talking to him because I am gathering information and will be ready to squash him once I have proof.) I'm seeing more and more that he is one of those men who has to blow up everything he has/does to make you think he is really hot stuff.  And he's not too bright.  And he's an ass.  And he keeps telling me that his dog hates other dogs and will kill another dog if it has a chance. 
Really, Mr. White-Trash Boyfriend?  Really?
So I'm in high alert.  And I'm watching my dog very, very carefully.