When comparing prices, you must look beyond the surface and evaluate the steel grade (e.g., Q235 or Q345), as higher-grade steel offers better load-bearing capacity. The surface treatment is a major price driver; Hot-Dipped Galvanized (HDG) is more expensive but offers superior corrosion resistance compared to Pre-galvanized or Painted finishes. Additionally, verify the wall thickness (standard is often 3.2mm or 4.0mm) and outer diameter, as even a 0.2mm difference can significantly impact both the price and structural safety.