The price of underwear is primarily driven by fabric composition, GSM (grams per square meter), and construction complexity. For high-end markets, prioritize Long-staple Cotton, Modal, or Bamboo fibers, which command a higher price but offer superior breathability. Ensure the GSM is between 160-200 for a balance of durability and comfort. Always verify if the price includes OEKO-TEX Standard 100 certification, as compliance with chemical safety standards is a non-negotiable value-add for international trade.