You can keep track of the listings you've shown a prospect using the Dates & Comments form in the Prospect Cart.
In the Prospect Cart, select either the Saved or Rejected tab. Then click Dates & Comments. Type in the date you showed a property and any comments you want to note, then click Submit. This information displays below the listing in the Prospect Cart, for your reference.
NOTE: You cannot enter dates and comments for listings in the Newly Matched tab of the Prospect Cart. Move the listings to either the Saved or Rejected tab first.
See also
Saving listings for a prospect