Include Port Expense in 'Port - Cargo History' & allow right-click to Cargo History from Estimate
It would be incredibly helpful to get some information on past Port Expenses in the Estimate to help with accurate Estimates without needing to go outside the system.
Proposal - in the Estimate, once the Vessel, Cargo, and possible some other info is filled in, allow User to right-click on the Port and get an option for Past Port Expenses, based on the aforementioned criteria.