THEM: i'll take one of each.  YOU: what if i take two balls and the book?  THEM: you gotta give me another ball for the book.  YOU: what if i keep all of the balls and you take the book and hat?  THEM: no deal  YOU: what if i take two balls and the hat?  THEM: no deal  YOU: what do you want?  THEM: one of each.  YOU: no deal.