When sourcing container houses, prioritize the structural frame material, typically Q235 or Q345 galvanized steel, to ensure corrosion resistance and a lifespan of 20+ years. The wall panels should use high-density Sandwich Panels (EPS, Rock Wool, or PU); Rock Wool is preferred for its Class A fire rating and superior thermal insulation. Additionally, verify the floor loading capacity, which should be at least 200kg/m² for standard residential use, and ensure the roofing system features an integrated drainage design to prevent water leakage.