When purchasing greige fabric (unbleached and undyed cloth), you must prioritize yarn count (e.g., 20s, 30s, 40s) and thread count (TPI/EPI), as these determine the final product's density and strength. Ensure the composition (e.g., 100% Cotton, Poly-Cotton blends, or Linen) matches your end-use requirements. Additionally, verify the GSM (Grams per Square Meter) to ensure weight consistency and check for weaving defects like reed marks or oil stains, which can affect the subsequent dyeing and finishing processes.