Prioritize network reach (transit times to customers), warehouse scalability (storage and labor flex), service scope (kitting, returns, same‑day/next‑day pick), technology (WMS, APIs, EDI), SLA and penalty terms, and verified carrier contracts. Review historical throughput, seasonal elasticity, and integration testing timelines before committing.

Expect access to major highway corridors and intermodal options that reduce regional transit times, concentrated LTL and parcel lanes for cost‑efficient routing, and local carrier networks that support dense last‑mile delivery. These features help optimize routing, enable zone‑skipping, and improve delivery reliability.

Key cost drivers include real estate and labor rates, utility and fuel costs, handling and pick labor, and accessorial fees. Evaluate pricing models for storage, transaction fees, and accessorials; model scenarios for peak season volume, shrink, and return rates to compare total landed cost rather than headline per‑order rates.

Omnichannel and B2B needs demand tighter inventory visibility, multi‑channel order orchestration, configurable slotting, and value‑added services (kitting, pallet build, EDI/EDI‑API). Ensure the 3PL can segregate inventory, support multiple service levels, and provide real‑time reporting and SLA governance for both retail and wholesale flows.