Legal advice, verbal abuse?

I used go live with my mother and her boyfriend (who is bipolar but refuses to take meds or acknowledge this, he was on meds at some point and time for it during his life). He is verbally abusive and has psychotic tendencies. He will be okay one moment and in a full blown rage another from the simpliest things such as a unclean room or a simple question. Last year I moved out because I could not take it anymore, he pushed me and annoyed me to take a stupid air conditioner that had been at the house so I did. I now have to return said ac and I couldn't afford this and I explained it and he went into a psychotic break, called my boyfriend house repeatedly only to scream "you will return this do you understand it is mine it belongs in my house you took this" repeatedly. I did not take it he annoyed the sh*t out of me to take it and doesn't remember because he goes into these rages. I have clothes and other personal items in the house and he said that if I set foot on the property he will shoot me and call the cops..I'm bring the ac back tomorrow but I'm afraid once I do he won't let me get my personal items because it is ""his house"" which he has said before is tghat legal? . can I request that all of my things be taken out and then I will return it ? I need legal advice on this as I want my things back. Please help. He's looney like off his rocker and I'm not the only one that knows..as an example he once went out back of our house and took a shotgun to about 6 cats and then lined them up execution style on our deck for my mother to see as she is a ridiculous cat lover because he left his garage door open and one got in and knocked over a motorcycle helmet...someone please help