Here's How:
Ask to see all paperwork and documentation.
Make sure the VIN matches other VIN's on the vehicle and paperwork (original/no alterations)
If the car has been restored, ask for any pictures taken before, during and after
Check service history for repairs, oil changes and scheduled maintenance
Start the car.
Check for smoke coming from the exhaust
Listen to the engine idle quality when cold and hot
Rev the engine; is it smooth? Document any noises
Keep it running until the engine is hot and check for exhaust smoke again
Take the car for a road test.
Inspect engine performance and acceleration
Listen for engine noise at high/low speeds
Listen for automatic transmission/transaxle noise
Is the automatic transmission shifting smoothly
Listen for drive axle and transfer case bearings or gear noise/vibration
Check the manual clutch for engagement, chatter or slippage
Test the steering for responsivness/smoothness/play
Test brakes for effectiveness/operation/noise/pulling
Check gauge operation; Speedometer/Tachometer/Odometer
Document temp/oil/battery gauges when hot and cold
Check the suspension on a rough road
Visually inspect the exterior.
Check everywhere for rust
Visually inspect for repairs or damage
Check body panels for dings, dents, alignment, mismatched paint and overall paint condition
A magnet can detect any filler used in repaired dents
Inspect for chrome damage, alignment and improper repairs
Open and close doors/hood/trunk/tailgate for proper operation
Inspect grill/trim/molding for bends, dings, missing parts and proper attachment
Inspect the windshield and side and rear windows for damages, pitting, repairs, wiper marks or cracks
Check the mirrors condition and hinge operation
Check to make sure all interior/exterior lights are operational.
Head lights, high and low beams
Tail lights
Brake lights
Parking lights
Hazard lights
Reverse lights
Turn signals
License plate lights
Fog/Driving lights
Interior lights
Dashboard lights
Check for cracked or clouded lenses
Inspect the interior.
Are the seat belts operational?
Test audio/alarm/speaker systems
Test heating/ventilation/AC/defogger/defroster
Is the clock keeping time?
Check the horn
Inspect the lighter/power outlets condition/operation
Inspect glove box/glove box light/hinges
Inspect armrest/console condition/operation
Is steering tilt/lock operational?
Check rear view mirror condition
Check fuel filler door release
Check that all door handles operate
Inspect interior trim/carpet/floor mats/door panels/headliner/sun visors
Make sure that the automatic/manual door locks are functional
Inspect all leather/vinyl/material.
Check the condition of seat upholstery for wear/rips/cracks/fading/stains
Check the dashboard/door/headliner for splitting or water damage
Inspect sunroof/moon roof/convertible top
Inspect convertible tops condition/operation/fit
Check convertible top boot
It’s time to open up the hood.
Check for oil leaks
Inspect air filter for oil
Check the oil for water/sludge/clarity/level.
Inspect timing belt/chain.
Check all fluid levels.
Inspect belts for wear and fraying.
Check hoses.
Inspect wiring.
Inspect engine mounts.
Look for water pump leaks.
Pressure test radiator cap.
Look for fuel pump leaks.
Inspect fuel filter.
Kicking the tires.
Inspect tires for correct size/tread depth/pressure
Check the tires for abnormal wear
Inspect condition of valve stems
Do all the tires match?
Does the spare match?
While you’re checking the spare, inspect luggage compartment for rust
Is there a jack or tools?
Don’t forget the car’s rubber parts
Check windshield wipers condition
Inspect interior and exterior rubber trim for splitting
