used-car-decoder

Used Car Decoder Skill

A used-car listing is a document written by someone who knows the car's

problems, for someone who doesn't. The dialect is learnable: "selling for a

friend" (distance from liability), "drives well for its age" (adjusted

expectations), "minor cosmetic damage" (photographed from the good side),

"no test drives without deposit" (walk away now). This skill decodes the

ad the way [[lease-decoder]] reads a lease — severity-ranked, money math

attached — then arms the viewing: the checks a non-mechanic can actually

do, the questions that surface evasion, and the honest boundary: which

findings mean pay a professional for an inspection and which mean leave.

What This Skill Produces

• A listing decode: phrase-by-phrase, 🔴🟡🟢, with what each hedge

typically means and the question that tests it

• The before-you-travel checks: history/title verification items

(accident/write-off status, finance owing, mileage consistency, recalls)

— each flagged as country-specific-verify-locally with what to search,

since registries differ everywhere

• A viewing & test-drive checklist ordered by cost-of-miss: the

cold-start, the panel-gap walk, fluids, tires including the spare-match,

electronics sweep, the specific listen-fors on the drive

• Seller questions that make evasion visible ("why selling?", "what

would you fix next?", "can I take it for a pre-purchase inspection?" —

the last one is the real test: honest sellers say yes)

• The money frame: comps from sold prices, what each found flaw is

worth in negotiation, and the walk-away list where no price is right

Required Inputs

Ask for (if not already provided):

• The listing text and photos described, plus price and the car

(make/model/year/mileage)

• The buyer: first car or fifteenth, mechanical comfort level, who else

might inspect with them

• Budget truth: the price ceiling including the first-year surprises

buffer (insurance, immediate maintenance)

• Country — for the verify-local flags on history checks and paperwork

(this skill never asserts registry procedures)

Framework

1. Decode the ad's dialect. Flag the classic hedges: liability

distance ("for a friend/relative") · condition adjectives doing heavy

lifting ("well for its age", "usual marks") · photo tells (no

full-front shot, wet-car photos hiding paint, interior only) ·

urgency pressure ("first to see will buy") · the deposit-before-

viewing 🔴s. Each flag gets its test question, not just suspicion.

1. Never travel before the paper checks. Mileage across ads/photos

consistent? History check run (accident, write-off category,

outstanding finance — finance owing can follow the CAR, not the

seller, in many places: 🔴 verify locally)? Recalls outstanding?

Seller matches the registered keeper? All flagged with what-to-search

terms, none asserted as universal procedure.

1. Inspect in cost-of-miss order. Ask for a cold start (pre-warmed

engines are a tell) → head-gasket-adjacent signs (mayonnaise under

the oil cap, white smoke — described plainly for a novice) → panel

gaps and paint-tone walk (accident repair) → tires including

date-codes and the spare (uneven wear = alignment or worse) →

electronics sweep (every window, warning-light theater: which lights

come on at ignition and go off) → the drive: straight-line braking,

full-lock turns, a listen with the radio OFF.

1. Let the questions do the work. The pre-purchase-inspection ask is

the sorting hat: "can my mechanic look at it?" — yes means proceed,

any version of no means the listing decoded itself. "What would you

fix next?" beats "any problems?" — everyone answers the second with

"nothing."

1. Frame the money before the feelings. Sold-price comps (not asking

prices) set the anchor; each finding gets its rough repair-cost class

(small/medium/engine-money — classes, not fake precise quotes) as

negotiation material. The walk-away list is absolute: finance owing

unresolved, write-off category undisclosed, no-inspection sellers,

mileage that doesn't add up. And the standing rule: the deposit

buffer for year-one surprises is part of the budget, not optional.

Output Format

## Listing decode
| Phrase / tell | Reading | 🔴🟡🟢 | Test question |

## Before you travel (verify-local items)
[ ] History check (search: …) [ ] Finance owing [ ] Mileage consistency
[ ] Recalls [ ] Seller = keeper — each with country-flag

## At the viewing (cost-of-miss order)
[The checklist with novice-friendly descriptions of each sign]

## Ask the seller
[The questions + what evasive answers look like]

## The money frame
[Comp anchor · findings → negotiation classes · the walk-away list ·
the year-one buffer line]

⚠ A pre-purchase inspection by a mechanic beats every checklist here for
engine/transmission health — budget for one on any car you're serious about.

Quality Checks

• [ ] Every decoded phrase quotes the actual listing — no generic

suspicion without a receipt

• [ ] All registry/history/paperwork items carry verify-local flags with

search terms, never asserted procedure

• [ ] The checklist is executable by the stated mechanical comfort level;

pro-inspection items say so

• [ ] Repair costs appear as classes, never invented precise quotes
• [ ] The walk-away list is present and absolute — items where

negotiation is explicitly the wrong response

Anti-Patterns

• [ ] Do not diagnose remotely — signs and their severity class, yes;

"that's definitely the clutch," no

• [ ] Do not assert country procedures (title transfer, history

registers, deposit law) — flag and route

• [ ] Do not let a good price override the walk-away list anywhere in

the framing

• [ ] Do not write the seller as an enemy — most are honest; the decode

exists to identify which kind is across the table

• [ ] Do not skip the pre-purchase-inspection recommendation because the

buyer is excited

Related

[[mechanic-quote-decoder]] for after you own it; [[car-lease-decoder]]

for the leasing route; [[car-tco]] for what this car really costs per

year; [[franklin-decision-ledger]] when it's down to two cars.