Prioritize proximity to major arterials and cross-border corridors, parcel and LTL hub access, typical lane transit times, and local pickup frequency. Also assess dwell-time history, route density for your top SKUs, and modal options (road/rail/air) to model true landed-cost impacts.

Confirm WMS/API compatibility, real-time inventory visibility, billing transparency, and support for automation or scale-up throughput. Validate SLAs for pick/pack/ship, error rates (inventory accuracy, order accuracy), onboarding timelines, and sample integrations with marketplaces or ERP systems.

Key cost drivers are inbound freight, storage rates, unit handling (picks, packs), DIM-weighted parcel pricing, and returns handling. Service metrics to monitor include transit time variability, on-time shipment rate, inventory accuracy and order-cycle SLA adherence—these directly affect landed cost and NPS.

Assess the 3PL's customs brokerage capability, bonded warehouse licensing, duty-deferral procedures, documentation accuracy, and experience with your product classification. Ensure clear processes for inward/outward customs movements and digital records to avoid clearance delays and compliance penalties.