Prioritize metrics that drive fulfilment performance: SLA adherence and on‑time pick rates, dock door and racking capacity, average order cycle time, inventory accuracy, and WMS API integration. Also assess transport lane density and seasonal staffing plans. Consider contractual terms for lead times on capacity expansion and clarity in billing for storage, throughput, and value‑added services.

Compare cost-to-serve across these dimensions: outbound transit times to key customer zones, parcel vs. pallet consolidation fees, warehousing unit costs (per pallet and per pick), and reverse logistics pricing. Model scenarios for peak season volume and average order value to quantify impact on delivery promise and margin.

Confirm road quality and proximity to primary distribution corridors, availability of scheduled carrier pickups, dock-door counts and handling equipment, and on-site staging for cross-dock operations. Validate carrier contracts and frequency for LTL, TL and parcel services to ensure required transit windows and capacity during peaks.

Seek a 3PL that offers real-time WMS/API integration with your OMS, standard KPI dashboards (OTIF, inventory accuracy, order cycle time), SLA penalties for missed commitments, transparent invoicing, and defined capacity expansion terms. Also review insurance, claims processes, and contingency plans for transport disruptions.