Outlook Email Time Analysis Based On Previous Responses?

So I support a 2nd inbox in Outlook (where all our clients come into) and there a multiple folders within it (which get moved after request/issue is completed). I need to figure out how to go to each folder, conduct a time analysis on when email was received and when it was acknowledged. Any ideas or suggestions would be appreciated! I know there are software apps that $$ can do this but as everyone - trying to save some $$.

Thank You!