Pre-Purchase Inspection: Cost and What's Checked

A pre-purchase inspection (PPI) is a paid check of a used car by an independent mechanic before you buy it. It is the one step in a used-car purchase that replaces guesswork with evidence, and a typical one costs a small fraction of a single major repair.

This guide covers what a good PPI includes, what it usually costs, how to arrange one with a private seller or dealer, and how to turn the results into a decision or a better price.

A PPI is a professional opinion on the car's current condition and what it will likely need soon. It typically takes one to two hours and ends with a written or emailed report, often with photos.

It is not:

• A guarantee. A mechanic cannot predict every future failure, and some problems only appear under specific conditions.
• A state safety or emissions inspection. Those are pass/fail checks against legal minimums, not a condition report.
• A history report. A PPI looks at the physical car; a history report from an NMVTIS (opens in a new tab)-approved provider looks at title brands and reported events. You want both.

Inspections vary by shop, so ask for their checklist in advance. A thorough one covers these areas.

Engine and drivetrain

• Cold-start behavior, idle quality, unusual noises
• Fluid levels and condition: oil, coolant, transmission, brake, power steering, differentials where accessible
• Leaks from gaskets, seals, hoses and the radiator
• Belts, hoses and the cooling system
• Engine and transmission mounts
• A compression or leak-down test, on request or if something seems off

Computer scan

• Stored, pending and permanent diagnostic trouble codes
• Readiness monitor status. Several "incomplete" monitors usually mean codes were recently cleared or the battery was disconnected, which can hide a problem.
• On some cars, module-level scans for airbag, ABS and transmission faults

You can look up any code the shop finds in our OBD code library.

Brakes, suspension and steering

• Pad and rotor thickness, caliper condition, brake lines
• Shocks, struts, control arms, bushings, ball joints, tie rods
• Wheel bearing noise and play
• CV axles and boots

Tires and wheels

• Tread depth on all four, and whether wear is even (uneven wear points to alignment or suspension issues)
• Tire age from the DOT date code (the last four digits show week and year)
• Matching brands and sizes, especially important on all-wheel-drive cars

Body, frame and underbody

• Signs of prior accident repair: paint thickness differences, overspray, uneven panel gaps, replaced bolts
• Frame and unibody damage or kinks
• Rust on the subframe, rockers, brake and fuel lines
• Signs of flood damage. If you are worried about water, tell the shop. See how to spot flood damage.

Electrical and interior

• Battery and charging system test
• Lights, windows, locks, mirrors, seats, HVAC, infotainment
• Warning lights at startup (each should illuminate briefly, then go out)

Road test

• Transmission shifts cold and warm, at light and heavy throttle
• Pulling, vibration, steering play, brake feel
• Noises over bumps and in turns

Prices depend on the shop, region and type of car. Treat these as typical estimates that vary by vehicle and region:

Call two or three shops and ask what is included. The cheapest option is not always the best; the detail of the report matters more than a small price difference.

• An independent shop you choose. Not the seller's mechanic, and not a shop the seller recommends.
• A brand specialist for European, luxury, diesel, hybrid or performance cars, where known failure points are model-specific.
• A dealer service department for the brand, which can also check whether recall work and software updates were done.
• For used EVs, a shop that can read the battery's state of health. See our used EV battery guide.

If you need a shop near the car, look for well-reviewed independents with ASE-certified technicians, and ask whether they do PPIs regularly.

With a private seller

1. 1Ask early, on the first call: "Would you be okay with me taking it to a mechanic before buying?"
2. 2Book the appointment yourself, near the seller, at a time that works for them.
3. 3Either drive the car there together, or meet at the shop.
4. 4Do not hand over a deposit until after the inspection, or agree in writing that the deposit is refundable if the inspection finds problems.

A seller who refuses a PPI is the biggest red flag in a private sale. Walk away.

With a dealer

Most reputable dealers allow off-site inspections, sometimes with a salesperson along or with a mobile inspector coming to the lot. Be wary of a dealer that only allows its own "certified" inspection. A dealer's multipoint inspection is not independent.

Give the mechanic a head start:

• Decode the VIN with our VIN decoder so you know the exact engine and transmission.
• Look up the model year on our research pages for common complaints, and tell the shop what to look at.
• Check open recalls for the VIN on NHTSA's recall lookup (opens in a new tab). Recall repairs are free at a dealer.
• Note anything you noticed on your own test drive.

Sort every finding into one of three buckets:

For negotiable items, ask the shop for a written estimate. Present it to the seller calmly and ask them to either fix it or reduce the price by roughly that amount. Our maintenance cost tool helps you sanity-check what upkeep will look like over the next year.

If you buy the car, keep the PPI report. Add it, and any records the seller gives you, to your free garage so the car's history starts on solid ground.