If an organization has agreed to sell tickets on your behalf, you have a few different options for adding an organization as a seller.
Adding Sellers
Option One: Add an organization as an External Seller while you create an event
When creating an event you will have the options to "Save & Finish" or "Save & Edit Sellers"

If you select Save & Edit Sellers it will take you to a page that lists the different tickets types available for the event. You can search and add different organizations to sell the different ticket types. As an example, you may allow a specific organization to only be able to sell VIP tickets, not General Admission tickets.
Note that the organization must be registered on Showpass to be added as a seller.
Once you have selected the Organizations that will be able to sell tickets, click Finish. Now those organizations have access to selling tickets.

Option Two: Add an organization as an external seller after you've created the event
If you would like to add sellers once the event has already been created, you can click the gear box in the right hand corner of the event and click on the Edit Sellers option.

It will redirect you the page that lists the different tickets types available for the event. From here, you are able to choose the organizations you wish to have access to selling the different ticket types. Once you're done, click Finish. Now those organizations have access to selling tickets.
Editing Payment Options
For both options above, you are also able to select the type of payment each organization can accept (cash/credit/both). If the cash and credit circles are coloured (blue for cash and green for credit), that indicates that the form of payment is accepted. Under the organization, along with the payment type, you are able to set up a selling limit for each organization.

Stats Access
You have the option to provide your external organizations the ability to have Stats Access or not.
This is what the External Organization will be able to access if they do not have full Stats Access:
This is what the External Organization will be able to access if they do have full Stats Access:
The main difference is the ability to download the Will Call CSV for all guests as an external organization. Whether an organization has full Access Stats or not, they will only be able to see the Transactions they have made (not the entire events Transactions).