You can create another table, something like "Saved_Items" and it would have columns like, User_ID, Item_ID, etc. This could be a child table of your User table and Item table.
Then, have a customized button that when clicked will saved the details in this table. You can use an auto-submit form to to this
Then, create another Report DataPage, where you will filter the contents of the table using the User_ID (you can use the authentication if you have) to show the saved items.