Buyers must prioritize Base Material quality (e.g., FR-4, High-TG, or Aluminum substrates) and Layer Count (Single, Double, or Multi-layer) to ensure thermal stability. Key parameters include Copper Thickness (typically 1oz to 3oz), Surface Finish (HASL, ENIG, or OSP for oxidation resistance), and Minimum Trace/Spacing (e.g., 3/3 mil for high-density designs). For PCBA (Assembly), verify the SMT (Surface Mount Technology) precision and the capability to handle components like BGA (Ball Grid Array) with X-ray inspection.