Yeah Chihuahuas can be little bastards! I used to tell people that if you're gonna fight dogs why not Chihuahuas? They're already mean and it would have to be funny as midget wrestling.Chihuahuas are the most aggressive dog bread there is. Difference is when they go after you its a whole lot easier to fend them of than it is 100lb pit bull..
Most places I rented from had a weight restriction and it was always in my mind sound. They were pet friendly as long as the pet was under 50lbs. Their reasoning was that all pets have the capacity to be aggressive or docile but the larger the dog the more likely that they will do damage should they get aggressive for whatever reason. The complex had a lot of kids and a lot of older people and they also didn't want the dogs to jump on someone and knock them over on accident trying to lick their face or get attention. They did have a leash rule but lets face it, leashes can break and do from time to time, and every once in a while that dog is going to sneak out the door on your way out or in if he/she really wants to. I love my pups and always accepted when I adopted them that they might make it difficult for me at times, its all just a part of pet ownership.