My new dog. Worth taking to the vet?

I feel extremely bad for Ash. Aggression as bad as his shows that he is afraid of the world. Seeing as he is putting Max, you, your husband, your cats, and your kids in danger, I recommend taking him to your local animal shelter. They can find a foster home for Ash that will work on his aggression with him, and then he will be adopted to a new forever home. Make sure the shelter you bring him to is a no-kill shelter. If it's a kill shelter, I guarantee they will kill Ash simply because he's fearful.