A junior account manager owns an account and creates a new opportunity to manage a complex deal. She needs the help of the product specialist and solution engineer. Given the size of this deal, she knows the account is likely to be reassigned to a senior Account manager in the near future.

What is the optimal way for the Junior Account manager to share the opportunity, given the private sharing model?

Manual share on the account
Opportunity Team
Manual share on the opportunity
Create owner-based sharing rule