Which related lists should primarily be used to capture financial data in a project?

Cost Plans and Monetary Benefit Plans are the related lists that should primarily be used to capture financial data in a project. Cost Plans allow you to define the expected costs of a project over time, based on the planned and actual work, resources, and expenses. Monetary Benefit Plans allow you to define the expected financial benefits of a project over time, based on the estimated and realized value, revenue, and savings. You can find more information about these related lists in the Product Documentation for ServiceNow.