Request zone‑by‑zone transit time matrices, carrier on‑time percentages, order cut‑off vs ship time data, average dwell and cycle times, parcel density maps, and historical seasonal volume variance. Compare these with your SLA targets to validate network coverage and expected delivery windows.

Prioritize facilities with modern racking, adequate dock doors and trailer parking, dedicated returns processing, batch/pick‑and‑pack capabilities, WMS with API/EDI support, and options for automation or scale‑up space to handle peak seasonal spikes.

Local 3PLs often offer lower fixed costs and more flexible minimums; national providers may provide better carrier rates and network discounts. Key drivers include storage tiering, pick/pack fees, inbound handling, minimums, fuel/SCAC surcharges, and charges for value‑added services.

Define target KPIs (OTIF, order accuracy, average pick time, dwell), agree on data exchange formats and test transactions, perform pilot SKUs and mock orders, document SOPs, set escalation paths, and schedule phased cutovers with capacity validation and contingency plans.