Assess SLA targets (pick/pack accuracy, order cycle time), throughput capacity, slotting and storage types, WMS functionality and integrations, security and audit controls, and evidence of continuous improvement. Request site visits, performance reports, and references to validate daily operating cadence and exception management.

Review carrier density and scheduled services for the region, availability of LTL consolidation lanes, typical transit times to major metros and ports, fuel and accessorial structures, and the 3PL's carrier relationships. Reliable pickup windows and consolidated routing reduce per-unit cost and variability.

Include storage (per-pallet and per-SKU), inbound receiving and put-away, pick-and-pack labor, outbound freight to customers, returns handling, inventory carrying costs, slotting and rework, and any integration or onboarding fees. Model scenarios for seasonality and scale to capture true landed fulfillment cost.

Require a modern WMS with API/EDI connectivity, ASN and pallet-level tracking, reporting and dashboard access, batch and pallet management, customizable pick strategies, and support for EDI purchase orders and invoicing. Confirm integration testing plans and data reconciliation procedures.

Conduct site audits, validate insurance and security, run a staged pilot or parallel operations, define KPIs and penalties in the SLA, establish inventory reconciliation cadence, document contingency plans, and agree a phased cutover with training for systems and processes to limit disruption.