What I would do, if I were the father, would be to go door to door with the toy, explain to the adults, and see what they thought. If they weren't going to participate or be home, then move on. If they were gonna be home but seemed hesitant, didn't want to deal with it, then move on. If they *were* willing, then give them the toy, and write down that address. Then later, when trick-or-treating with his son, go only to the houses with addresses on his list, and have his son introduce himself. That way, only houses who have agreed to participate have a toy to begin with. There's no need to return the toy, there's no feeling guilted into it if somebody just doesn't want the trouble, or if the person who will be giving out candy won't be available until the last minute and there won't be time to explain it to them, etc.