answer: #Person2# wants to go to Collin's garage sale but changes mind to the flea market after hearing #Person1#'s suggestion.
documents: #Person1#: Are there any changes in this morning's program?
  #Person2#: No, we'll go to Collin's garage sale; he has many books for sale.
  #Person1#: There're so many books for sale in a flea market near this street, too. Why don't you go there?
  #Person2#: What is a flea market?
  #Person1#: It is not that different from other markets except that the goods there have been used before.
  #Person2#: Are there any good books?
  #Person1#: Of course. If you're lucky, you can find some rare and old ones.
  #Person2#: It sounds like a good place and we should go there.