skills/used-car-investigator/references/listing-forensics.md

# Listing and VIN Forensics

## Seller-language flags

Treat these as prompts for verification, not proof of wrongdoing:

- "needs nothing"
- "recently serviced" without invoices
- "minor accident"
- "easy fix"
- "mechanic special"
- "as-is"
- "price firm" paired with obvious unresolved work
- "selling for a friend/family member"
- "don't know much about cars"
- "lost the receipts"
- "engine replaced" without provenance
- "new transmission" without invoice/specification
- "only needs sensor"
- "check-engine light is just..."

## Curbsider/flipper indicators

Look for clusters, not one clue:

- very short ownership
- seller has many vehicles listed
- vehicle not registered to seller where legally relevant
- repeated background/location across many listings
- temporary plates or unexplained plate removal
- vague service history
- quick cosmetic reconditioning
- title/ownership paperwork ambiguity

## Photo forensics

Check for:

- inconsistent seasons/locations
- auction-yard markings
- missing VIN labels
- mismatched wheels/panels/interior trim
- panel-gap or paint mismatch
- airbag/SRS lights
- warning lights during ignition-on state
- uneven tire wear
- rust locations
- fluid stains
- low-resolution or reused stock images

Do not claim image manipulation unless evidence supports it.

## VIN/history reconciliation

Create a timeline ordered by date:

- registration
- mileage
- service
- accident/claim
- auction
- listing
- title/brand event
- ownership change

Flag contradictions rather than smoothing them over.

## CARFAX/report handling

If a report is supplied, distinguish:

- events explicitly reported
- service records
- claims/estimates
- registration/title information
- gaps with no data

"No accident reported" means the report contains no reported accident; it does not prove no accident ever occurred.

## Accident discount

Do not use a universal percentage. Discount depends on:

- severity
- structural involvement
- quality/documentation of repair
- vehicle age/value
- market stigma
- warranty/CPO eligibility
- future resale implications

## Marketplace handling

### Facebook Marketplace
Pages can be inaccessible without authentication. Use screenshots/pasted listing data when needed and independently research VIN/powertrain/market comps.

### AutoTrader / Kijiji
Extract listing metadata, seller type, price, mileage, trim, description, and VIN when available. Cross-check dealer claims and compare local comps.

### eBay Motors
When possible, distinguish active asks from sold/completed listings. Review seller feedback and description inconsistencies when relevant.