We will use a megohmmeter (insulation resistance tester) to measure the insulation resistance of the high-voltage bus. If the resistance value is below the national safety standard, it indicates a risk of leakage, and the vehicle will be deemed unqualified.

Obtaining precise internal resistance at different SOC levels requires disassembling the battery pack and connecting it to a professional charge-discharge cabinet for several days of cycling tests. This is beyond the scope of non-destructive used car inspections; we only provide real-time estimated internal resistance data based on OBD port readings.

Start with the paperwork: the vehicle registration certificate lists every ownership transfer, and the service book plus dealer maintenance records help confirm mileage. For digital verification, ask the seller for a live video walkaround plus a diagnostic scan report showing the ECU-recorded mileage, which is hard to manipulate. For EVs, request a battery state-of-health (SOH) report — it reveals real usage patterns far better than the odometer. Finally, a pre-shipment inspection by a third party should include structural checks (pillars, chassis rails) to rule out accident repairs. Build "no major accident, no flood or fire damage" into your purchase contract with a refund clause if the inspection contradicts it.