Prioritize a WMS with real-time inventory visibility, API/EDI connectivity for carrier and marketplace integration, robust picking and packing workflows, and options for automation or scalable labor. Verify uptime, security, and reporting capabilities to match your SLA and growth plans.

Evaluate proximity to national highways and rail nodes, average transit times to primary customer ZIP clusters, availability of express parcel and LTL carriers, and ease of access to ports or intermodal terminals if export or long-haul rail is required.

Compare storage rates (per pallet and per sku), pick-and-pack fees, inbound receiving charges, outbound freight handling, value-added service costs (kitting, labeling), minimums, chargeback rules, true-up billing cadence, and SLA penalties for service shortfalls.

Require daily inventory reconciliation, real-time sync between your OMS and the 3PL WMS, defined return processing SLAs, segregation of return disposition (refurbish, restock, dispose), and transparent reporting on return reasons and RTO rates to inform product and channel decisions.