Locale switching forces servers to return market-specific content—language, date formats, and airport naming—so downstream systems don’t misinterpret results. Reliable currency parsing captures base fare, taxes, surcharges, and FX conversions exactly as shown to local shoppers, preventing reconciliation gaps in pricing engines. Full dynamic JavaScript rendering reproduces client-side fare assembly and calendar widgets, revealing seat buckets, blackout dates, and promo logic that static fetches miss.