Require a WMS with real-time inventory, SKU-level traceability, and carrier integrations; documented SLA for order accuracy and lead times; scalability for peak velocity; cold-chain handling if needed; and reverse-logistics/returns processing. Also verify staffing, security, and reporting cadence for continuous performance monitoring.

Model landed cost using carrier rates, zone-based transit maps, and port-drayage fees; compare facility rent and labor costs versus savings from reduced transit times; factor in cross-dock or consolidation options; and stress-test scenarios for peak season and expedited lanes to quantify total delivered cost.

Negotiate clear KPIs for order accuracy, on-time shipments, inventory accuracy, and receiving cycle times; define chargeback policies, minimums, and notice periods; require transparent monthly billing with activity-level detail; and include service credits and exit terms tied to measurable performance.

Use API or EDI for real-time inventory and order flows; agree on message formats and cadence (inventory sync, order acknowledgements, ASN); run comprehensive integration testing and mapping for SKUs and locations; establish backup data exchange and scheduled reconciliation to prevent stock discrepancies.