Buyers should prioritize fabric weight, typically measured in ounces (oz). For durable workwear, 12oz to 14oz heavy-duty denim is standard, while fashion-forward overalls often use 8oz to 10oz lightweight denim. Ensure the composition meets your needs, such as 100% cotton for authentic feel and durability, or cotton-spandex blends (2-3% elastane) for added comfort and stretch. Additionally, verify the wash process (e.g., stone wash, acid wash, or enzyme wash) to ensure color consistency across bulk batches.