Buyers must prioritize Max Drilling Diameter and Max Drilling Depth to ensure the machine meets project requirements. For Horizontal Directional Drilling (HDD) rigs, the Pullback Force (kN) and Spindle Torque (N.m) are critical for overcoming soil resistance. Additionally, verify the Engine Power (kW) and whether it uses reputable brands like Cummins or Steyr for global maintenance accessibility. For stationary horizontal boring machines, check the Spindle Speed Range and Table Load Capacity to ensure structural stability during heavy-duty operations.