How to Restrict Visibility of Tasks / Uploads

I'm a Creative director using Wrike to manage graphic design project requests from clients, and my general work flow. My clients (collaborators) will use a project request form to submit a job ticket to us. When they do so, they are automatically shared to that project. However, my concern is that as we go through initial rounds of design, I want to use Wrike to upload those early design versions and make edits and changes privately with my design team without them being visible to the client. When we are ready to present the design to the client for review, I want to be able to loop the client in to see, make comments, and request revisions of their own.

I can't see a way to do this without removing the client from the project. But doing that will remove the client's ability to check on the status of the project, which is a feature we really like about Wrike. 

Clients shouldn't see the messy design process and back and forth that is handled internally. I'm concerned my only option will be to keep those initial back and forth designs outside of Wrike and handled in email, but that sort of defeats a big part of the purpose of using Wrike in the first place.

Thoughts? Help?

Thank you!