Prioritize SLA metrics (order cycle time, on-time shipping), pick/pack accuracy, inventory turnover, and return processing speed. Also evaluate WMS integration, carrier connectivity, scalability, and transparent billing. These criteria drive fulfillment reliability and predictable landed cost.

Proximity to primary highways and intermodal points reduces road miles and freight cost; locations nearer to carrier hubs offer more daily pick-up windows and faster last-mile delivery. Site selection should balance customer density, carrier lane availability, and access to cross-dock facilities.

Require a modern WMS with API/EDI connectivity, barcode scanning, configurable SLA reporting, and support for batch/kitting and returns workflows. Check for appropriate racking, climate control where needed, security controls, and quality assurance processes to maintain inventory integrity.

Smaller brands can use 3PLs cost-effectively by choosing flexible pricing: per-pick and per-shipment fees, tiered storage rates, and bundled onboarding credits. Expect receiving and minimum monthly handling fees; negotiate volume thresholds and pilot periods to align cost as you scale.