Worked on the odoo/odoo repository to enhance the accuracy of landed cost and stock valuation processes by addressing vendor refund handling. Focused on backend development using Python, the work involved delivering a targeted bug fix that preserved the sign of vendor refunds in landed costs, preventing inflated stock valuations. Adjusted the price unit calculation logic to ensure refund amounts were correctly negated, and implemented unit tests to verify that refunds properly reduced stock valuation. This approach improved the reliability and auditability of landed cost accounting, strengthening financial reporting and ensuring that core Odoo accounting logic handled refunds as intended.