Default the sales rep on the Salesforce CPQ Quote object

Follow the steps below to use the DefaultSalesRepID special field

1. Create a custom formula text on the Quote object with an API name of "DefaultSalesRepId__c"
2. Verify the Quote's Sales Rep is correctly set using the DefaultSalesRepID field value

1. Create the DefaultSalesRepID field

1. In Salesforce Lightning, navigate to Setup.
2. Click Object Manager.
3. Navigate to the Quote object.
4. Navigate to Fields & Relationships and click New Field.
   1. Field Data Type: Formula
   2. Field Label: Default Sales Rep
   3. Field Name: DefaultSalesRepID
   4. Formula Return Type: Text
   5. Formula: Build a formula for this field that contains the User ID of a user. For example referencing $User.ID defaults the Sales Rep to be the creator of the quote. SBQQ__Account__r.Owner.Id defaults the Sales Rep to be the Account's Owner. SBQQ__Opportunity2__r.Owner.Id defaults the Sales Rep to be the Opportunity's Owner. 
5. Set field level security for field. Click Save.
6. Set page layouts for field. Click Save.

2. Verify the Quote's Sales Rep is populated correctly

1. Create a Quote. Please note the DefaultSalesRepID field only populates the Sales Rep field upon Quote creation.
2. During the Quote creation process verify that the Quote's Opportunity (SBQQ__Opportunity2__c) field is populated before the Quote is saved.
   1. Note: If the Quote's Opportunity field is not populated, the DefaultSalesRepID field will not populate the Sales Rep field.  
3. Save the Quote
4. Verify the Sales Rep field has been populated and the Quote's DefaultSalesRepID field's value matches the UserID of the Sales Rep