THEM: howdy, could i have the book and the two balls?  YOU: i can give you two balls  THEM: so you want the book and the three hats?  YOU: yes  THEM: what else you got.  YOU: three hats and one ball?  THEM: i either have to walk away from this with 3 hats and two balls or the book.  YOU: i can't give you that. no deal  THEM: well the book is worth a lot to you and the rest is worth near nothing to me so thats about all i can come up with that doesn't screw me over.  YOU: i think i agree  THEM: so no deal all around.