I like to create a sawed off shotgun, a couchman, to use in my wild west shows. I know that there is a tax that needs to be paid, about $200, that you have to pay on the finished product. My question is do I have to go to an official licensed gun smith or can my friend, who is a hobby level gunsmith, do the work after the tax is paid on the receiver? If I do have to go to a gun smith does he need to be a NFA manufacturer. Where do I go to pay the wonderful tax on it .