When sourcing lady dresses, the fabric is the most critical cost and quality driver. You should prioritize fabric weight (GSM) and composition (e.g., silk, polyester, cotton, or spandex blends). For high-end garments, ensure colorfastness to washing and light meets Grade 4 or higher. For functional or summer dresses, verify breathability and moisture-wicking properties. Always request a fabric swatch book or a pre-production sample to check for 'hand-feel' and ensure the material does not suffer from excessive pilling or shrinkage (standard should be <3%).