From National Interest:

Gun owners would have two choices: either surrender their property to the government or pay a $200 tax to keep each item, which will be added to a national registry. For many people, this would quickly turn into thousands of dollars paid to keep their own property. A hunter, for example, with just one AR-15 and four standard capacity magazines would owe the federal government $1,000. Failure to comply could mean up to ten years in federal prison and a $10,000 fine.