Selecting low-cost building materials requires a balance between initial acquisition price and long-term durability. Focus on standardized specifications to reduce customization costs. For structural components like steel or cement, verify grade certifications (e.g., ASTM, EN, or GB standards). For finishing materials like ceramic tiles or SPC flooring, prioritize wear-resistance ratings and water absorption rates. Always request batch test reports to ensure that 'low cost' does not translate to 'low safety'.