Assess transit times to customer clusters, dock and staging capacity, available pallet positions and racking, labor pool and shift flexibility, and the 3PL's ability to scale headcount or temporary storage during peaks. Validate WMS performance, onboarding timelines, and minimum volume commitments to avoid hidden cost exposure.

Require API or EDI connectivity for real‑time inventory and order status, robust WMS with order routing, carrier integrations for last‑mile rates and tracking, returns management workflows, and performance dashboards for SLA monitoring and exception handling.

Key drivers include rent and occupancy, local labor rates, drayage and port fees, pick & pack fees, packaging and returns handling costs, and inventory holding charges. Control costs via density optimization, slotting, negotiated carrier contracts, and accurate volume forecasts to reduce chargebacks and detention.

Evaluate SLA metrics for order accuracy, on‑time dispatch, and dwell time; confirm access to regional and international carriers; review contingency plans for port congestion; require monthly performance reports; and include clear remedies or credits for missed SLAs to protect supply‑chain reliability.