To keep a separate property record for each appraiser, you can update the settings for your ACI Research Export. In ACI Report™, go to Comps>Export to ACI Research. Click the Settings button in the bottom right for additional options. Under Check for Duplicates, check the box for Entered By.
If the property is in the system already entered by a specific appraiser, it will perform the option you choose below: Overwrite, Do not update, or Prompt for user input.
Checking the Entered By selection for matching tells the database that the property is unique if it is entered by a different appraiser. Thus, allowing you to have the same property address with a different record in the database.