Vehicle EconomicsPre-Purchase Inspection Worth It Calculator
Weigh a mechanic's pre-purchase inspection cost against the expected value of what it might catch.
Why this comes up
A pre-purchase inspection costs $100 to $200 and catches mechanical problems a vehicle history report cannot, since it examines the actual vehicle rather than its paperwork. This engine runs the same honest expected-value framework as our Vehicle History Report engine, applied to a hands-on inspection's own distinct mechanism and probability.
How we calculated this
Expected value is your stated probability of the inspection finding a real mechanical problem, multiplied by the repair cost you would avoid catching it before purchase, minus the inspection's own cost.
Worked example, using this page's own defaults ($150 inspection, 20% chance, $4,000 avoided cost): run the calculator above to see the exact expected value and the break-even probability.
What this means
- An older vehicle, a private-party sale, or one you cannot test-drive extensively usually justifies a higher probability estimate.
- A used vehicle's purchase price is often ten to twenty times the inspection cost, so even a modest catch probability tends to clear the break-even easily.
- This does not replace the report a Vehicle History Report engine checks, run both for a significant purchase.
Limitations
This is not a guarantee any inspection will catch a specific issue, it models the expected value of your own honest probability estimate. See Methodology.
Methodology
This engine uses Vehicle Economics' break-even framing as a probability-times-avoided-cost expected-value model. See Methodology for the full detail.