The following records support Document Checklist Items out of the box in Financial Services Cloud:
Account: An Account is a record that represents a person or an organization that has a business relationship with your company. You can use Document Checklist Items to request and track documents from your account holders, such as identity proofs, tax forms, or contracts.
Residential Loan Application: A Residential Loan Application is a record that represents a request for a loan to purchase or refinance a residential property. You can use Document Checklist Items to request and track documents from your loan applicants, such as income statements, credit reports, or property appraisals.
Opportunity: An Opportunity is a record that represents a potential sale or deal for your products or services. You can use Document Checklist Items to request and track documents from your opportunity owners, such as proposals, quotes, or agreements. Verified Reference: : Salesforce Help Article 2 : Salesforce Help Article 3 : Salesforce Help Article 4

The following names are Association Type picklist field values:
Trust, which is a value that indicates that the accounts are related through a trust relationship.
Family, which is a value that indicates that the accounts are related through a family relationship.
Peer, which is a value that indicates that the accounts are related through a peer relationship.

Explanation
To give a group of users access to a Financial Deal, you need to share a financial deal record with a group by adding them as participants to the record from the Financial Deal Participants related list. The Financial Deal Participants related list is a custom related list on the Financial Deal object that allows you to add users, groups, or queues as participants of a financial deal. Participants can have different roles and access levels for a financial deal, such as Owner, Collaborator, Viewer, or Approver. By adding a group as a participant, you can grant access to all the members of that group for a specific financial deal. Verified References: : Salesforce Help Article [6] : Salesforce Help Article [7]

The following out of the box capabilities come with Financial Services Cloud Lead & Referral Management:
Referral Conversion: This capability allows you to convert a referral to an opportunity, a contact, or an account. You can use this capability to track the progress and outcome of a referral and measure its impact on your business.
Assigning a Referral: This capability allows you to assign a referral to another user, queue, or line of business. You can use this capability to route a referral to the appropriate person or team who can best meet the customer's need or interest.
Accepting a Referral: This capability allows you to accept a referral that is assigned to you or your queue. You can use this capability to acknowledge that you have received a referral and are ready to work on it. Verified Reference: : Salesforce Help Article 1 : Salesforce Help Article 3 : Salesforce Help Article 5