Prioritize measurable operational criteria: WMS integration and EDI capability, SLA and KPI commitments, dock and throughput capacity, inventory accuracy, returns and reverse logistics processes, and peak-season labor plans. Also assess proximity to major highways/carriers to optimize transit times and shipping costs.

Compare total landed cost metrics rather than rent alone: cost-per-order, inbound/outbound transportation, inventory carrying, labor rates, and value-added service fees. Model scenarios for seasonal demand and SKU velocity to reveal true cost trade-offs between nearby facilities and more distant consolidation nodes.

Require robust carrier connectivity, scheduled outbound appointments, cross-dock and consolidation services, and strong freight tendering processes. Confirm the 3PL's relationships with regional carriers and national networks, plus visibility tools and SLA penalties for missed delivery windows.

Validate regulatory and customs handling (if cross-border), WMS/WCS API compatibility, inventory reconciliation processes, disaster recovery and security controls, and documented scalability plans for peak volume. Include sample KPIs and a phased onboarding schedule to reduce operational risk.