My cockatiel is scared of EVERYTHING!!!

Ok, so we got Tango 3-4 months ago from a friend. He is about 3 years old. From what I saw he was afraid of his old owners. They said they didnt get him out much anymore and I assumed that was the problem. I have been working with him for 4 months now and I am soooo frustrated. He wont step up, he hisses when anyone comes near, he is afraid of his toys, he is afraid of everything!!!! He just sits on the picture frame in the bird room all day, and will fly around some, eat, then go back to the picture frame. Everyone in my family has tried if you try to get near him he hisses, bites then flies away. At this point when I got my conure she was perching on my shoulder and eating food right out of my hands. I just dont understand this bird. I am guessing that he was abused with his old owners and it just frustrates me to watch him sit there. I dont want him to be afraid of everything, I want him to interact and play with me but he wont. I know I should be patient but he should have made at least a little bit of progress by now. I dont know what to do and was wondering if anybody else has had this problem and could fix it. Should I go to an animal behaviorist or what? Is there anyting I can do to help?

I know it's frustrating but you can't show that to him. He's able to tell and as such you're reinforcing his behavior.

A helpful link I'd like to share but can't is the chair exercise by Sally Blanchard. There are also other helpful links on the site. I'd love to share it but because I'm on a Mobil device it won't be a good link. I'm sure you can find it googling:

The Chair Exercise By Sally Blanchard

Good luck and hang in there.

I basically go into a smaller room such as the bathroom to work with a scared bird. It's easier to contain in one area instead of catching them all over the place.