Prioritize measurable KPIs and infrastructure: transit-time SLA to target markets, dock and pallet throughput, WMS/API integration, inventory accuracy, and ability to perform value-added services (kitting, returns). Also confirm customs handling experience, carrier mix for last-mile reach, and scalable pricing tiers to match volume swings.

Choose 3PLs with documented customs brokerage relationships and routed transport experience. Verify bonded storage options, EDI for customs declarations, and proven workflows for duties and VAT recovery. These capabilities reduce clearance delays and unpredictable landed costs.

Look for a robust WMS with real-time inventory, multi-client tenancy, and API connectivity to your OMS/marketplaces. Service-levels to confirm include multi-SKU pick accuracy, same-day/next-day cutoffs, return processing SLA, and transparent billing. Tech and service alignment reduces exceptions and improves customer experience.