Prioritize WMS integration, inventory segmentation (dedicated vs shared), configurable pick/pack processes, returns management, and real-time reporting. Evaluate SLA terms for order cycle time, accuracy, and contingency handling during peak demand.

Closer proximity to major arterial roads and carrier terminals reduces drayage and linehaul costs and shortens delivery windows. A 3PL with carrier-neutral consolidation and scheduled dispatch can lower per-parcel rates and improve predictability across postal and private carriers.

Look for racked storage density, mezzanine capacity for kitting, climate control if needed, and dedicated packing zones. Metrics to enforce include on-time ship rate, order accuracy, inventory turn, and lead time variance for split-fulfillment strategies.

Model fixed vs variable charges (storage per pallet/m2, handling per pick, inbound receiving fees), seasonal minimums, labor overtime rates, and value‑added service fees. Include freight impact from regional carrier tiers and any technology or onboarding one-time costs.