I can understand how frustrating this is for you and your husband!! Sounds very stressful, and when you feel that he is behaving deliberately to manipulate you, that belief can cause you to feel even worse and more out of control!
My suggestion is this: I think this little fella has been through an awful lot. I think he's been through more than many adults have had to go through. AND, he doesn't have the coping skills that adults generally have by virtue of their years of experience with tough situations.
All behavior is needs-based. Because little children have such undeveloped verbal communications skills, it becomes a parent's job to interpret the behavior to discover the underlying need and help the child verbalize better and get their needs met. When children feel better, they behave better.
This little guy has had a lot of turmoil in his life, and my guess is that he is trying desperately to figure out his world and how to manage in it. He would benefit from knowing a few things:
1. That the adults are in charge and he is safe.
2. That his problems and needs are understood and that he can count on the adults around him to help him.
3. Better ways of communicating. He can benefit from you modeling appropriate ways of communicating when you are feeling angry, hungry, tired, frustrated, etc.
4. And, he can also benefit from your empathic listening. One thing that you can try saying to him is something like, "I know that you are hurting right now because otherwise you wouldn't talk to me like that. I want to help you. Can you tell me what you need?
Instead of telling him what not to do, try telling him what he can do! Instead of "no hitting the dog," try saying "The dog loves when you pet him."
As frustrated as you and your husband are, he is probably even more frustrated. You have more capacity for coping than he does, so I believe everyone will be happier if you can shift your perspective here and help him.
I hope that's helpful to you!!!