If an installer is using an in-house design team and sending the designs to an internal queue, these designs need to be approved by the sales rep before they can be used in a proposal.
To approve a design, view the customer's page and click "view design" on the design that needs approval.
Here the rep can choose to approve or request revisions to the proposal.
Some installers set their deals to auto-approve. If this setting is enabled, the rep does not need to approve the design before moving onto financing and agreements.