Prioritize SLA performance, pick/pack accuracy, inventory visibility (WMS capabilities), throughput capacity for peak periods, and carrier integrations for last‑mile and cross‑border lanes. Also evaluate facility certifications, security, and value‑added services like kitting and returns handling.

Primary cost drivers include storage density and racking requirements, labor rates and shift patterns, inbound/outbound handling complexity, packaging and returns processing, and transportation access that affects drayage and linehaul costs.

Reliable road networks and regional carrier density reduce last‑mile and intercity transit times, enabling tighter delivery windows. Multimodal links to ports and cross‑border carriers expand reach for export/import flows and can lower landed cost when integrated into an omnichannel routing plan.

Demand cross‑dock capacity, scalable pallet storage, a robust WMS with EDI/API integrations, staging and consolidation areas, and contingency labor plans. Verify the 3PL's experience managing volume spikes, long‑lead replenishment, and order consolidation for carrier cost optimization.

Agree on KPIs and SLA terms, run a phased implementation with test SKUs, validate WMS connectivity and EDI/API mappings, schedule parallel inventory counts, and define escalation and quality processes. A pilot period reduces risk and confirms cost‑to‑serve assumptions.