The behaviourist came to see Koda today!
It went really well, basically she said that we have to focus on all the things that Koda doesn't like (men, dogs, strange noises, skateboards etc) and i have to slowly bring them closer to him over time while i'm asking him to sit and look at me. The result we are hoping for is where something he doesn't like can go right past him and he doesn't even notice, he stays focused on me the whole time. This is all done at home, the next step (hopefully in a couple of weeks) will be to go out on a walk with the behaviourist and hopefully meet some other dogs and practice the learned techniques. I also learned that the breeder who i got him from could have actually planted the seed for his nervousness around some people because of the way she disciplined him as a pup