Professional Investigator 5 UPGRADE (single user) Cost: $79 Get the full version     Trial version     Developer's Website Contacting third-party download site please wait. If your download does not start, click here, or get the full version Descriptions Professional Investigator 5 UPGRADE (single user): This will upgrade a single-user Professional Investigator license to version 5. If you have additional user licenses, you will also need to purchase the appropriate upgrades for those users.