Hello @Baconguy! 

This is possible if you're using Employee Management! You would have to create a new role under the permissions tab. For this specific scenario I would enable Access Dashboard and toggle on Create, Manage, and Send Marketing Campaigns. 

When you assign this role to the ad agency they will only be able to create marketing campaigns on your dashboard. Just a heads up it will cost $5 dollars a month to add the ad agency as an employee. 

If you still have questions please feel free to reach out to me! I would be more than happy to help. 😊