Used Car Buying and Buyer Protection

Pre-Purchase Inspection Cost: What Each Type Costs and Misses

A shop check runs $186 to $273 and a mobile inspector $219.99. The price tracks how much of the car each one can physically reach, and nothing else.

September 8, 20269 min

Tips & Tricks

Car Inspection Cost: What You Pay and What Fails a Car

A US state inspection mostly costs $0 to about $60, and in many states the state sets the price. A stored fault code fails the emissions half on its own.

September 6, 20269 min

Will Your Car Pass the Emissions Test? Check Readiness Monitors First

A car can fail its emissions test for incomplete readiness monitors even with nothing wrong. Check them yourself for 15 euros before you book the test.

June 15, 20268 min

How to Check a Used Car Before Buying: The Full Checklist

Most used-car checklists cover paint and a test drive but skip the one check sellers fear: a 5-minute OBD2 scan that reads the faults the eye cannot see.

June 14, 20269 min

How to Negotiate a Used Car Price With OBD2 Scan Evidence

Two stored fault codes can be worth several hundred euros off the asking price. Here is how to turn a pre-purchase OBD2 scan into a documented discount.

June 13, 202610 min

Which OBD2 Codes Fail Inspection (And Why Clearing Them Fails Too)

Clearing a code before inspection resets the readiness monitors, and stations check those. The OBD2 codes that fail, and why a fresh clear fails anyway.

June 13, 20269 min

Recently Cleared Codes: How Readiness Monitors Expose It

A used car that scans clean can still have its codes wiped minutes before you arrived. Readiness monitors are how you catch it. Here is the check.

June 13, 20269 min

OBD2 Red Flags When Buying a High-Mileage Imported Diesel

A 210,000 km imported diesel that looks too clean hides its faults in the OBD2 data. Here are the red flags a scan catches before you wire the money.

June 13, 202610 min

VIN Decode Plus OBD2: The Two-Step Pre-Purchase Check

Decode the VIN to confirm the car is the spec the ad claims, then run an OBD2 scan to read its condition. Two steps, fifteen minutes, before you pay.

June 13, 20269 min

AdBlue Tampering: A 5-Minute OBD2 Check Before You Buy an EU Diesel

An AdBlue emulator or SCR delete is invisible on the dashboard but leaves stored DEF codes a generic OBD2 scan catches in five minutes.

How to Spot a Deleted DPF on a Used Diesel Before You Buy

A removed diesel particulate filter is illegal in the EU and costs about EUR 1,000 to 4,000 to refit. Six checks (three visual, three OBD2) catch it.

EGR Delete Detection: What OBD2 Will (And Won't) Show on a Used Diesel

A deleted EGR usually leaves the scan clean. Three things under the bonnet give it away, and putting the system back costs 250 to 2,200 euros.

How to Check a German Used Car With OBD2 Before You Buy It

A 15-minute pre-purchase OBD2 scan tells you most of what the seller of an imported German used car would rather you didn't ask. Here is the exact checklist.

Used Nissan Leaf: Battery Bars, SOH and Common Faults

Twelve battery health bars, the LeafSpy SOH number, and the four faults that kill resale on a used Leaf. What to check before paying 5,000 to 22,000 euros.

Tesla BMS Error Codes: A Used Buyer's Decoding Guide

BMS_a066, BMS_a067, BMS_u029 and the rest. What each alert means on a used Model 3, S or Y, how to check the pack, and the alerts that mean walk away.

Used BMW i3 Buyer's Guide: Battery Health and Range Check

Three battery generations, REX quirks, and four OBD2 checks that separate a healthy used BMW i3 from a tired one. Before you pay 8,000 to 28,000 euros.

BMW M57 Engine Buyer's Guide: 525d, 530d, 535d Faults

M57 vs M57N vs M57N2 across E60/E61. Swirl flap delete, twin-turbo 535d boost faults, ZF 6HP mechatronic. Five OBD2 checks before 3,000-12,000 EUR.

May 26, 202611 min

Used Audi A4 2.0 TDI Buyer's Guide: B8 vs B9, Quattro and Faults

EA189 B8 dieselgate legacy, EA288 B9, S tronic mechatronic, quattro drivetrain checks. The 5 OBD2 checks before you pay 9,000 to 35,000 euros for a used A4 TDI.

Used BMW 320d Buyer's Guide: N47 vs B47, Faults and OBD2 Checks

The 320d splits at the engine. The N47 hides its chain at the back, a 1,500 to 2,500 EUR job at an independent. Here is how to tell which one you have.

Used Mercedes Sprinter Buyer's Guide: OM651 Faults, AdBlue, DPF

OM651 timing chain and injectors, OM642 oil cooler, AdBlue countdown, DPF on stop-start duty. The 5 OBD2 checks before you pay 8,000-45,000 EUR for a Sprinter.

May 26, 202611 min

Used VW Golf TDI Buyer's Guide: PD, EA189, EA288 and Faults

1.9 PD vs 2.0 TDI CR EA189 vs EA288 across Mk5/6/7/8. Dieselgate fix legacy, DSG mechatronic, DPF on short trips. Five OBD2 checks before 5,000-22,000 EUR.

VW Passat 2.0 TDI Used Buyer Guide: DPF, DSG and Faults

EA189 vs EA288 vs EA288 evo. The dieselgate fix that still matters. DSG mechatronic, DPF, AdBlue and the five checks before you pay 8,000 to 22,000 euros.

Is It Safe to Drive with the Check Engine Light On?

Your check engine light just came on. Can you keep driving? It depends on whether the light is steady or flashing, and how the car actually feels.

March 18, 202610 min

Odometer Fraud: How to Detect Mileage Rollback (2026 Guide)

Odometer fraud costs EU buyers billions a year. How to spot mileage rollback from physical wear, OBD2 scans and vehicle history checks before you buy.

November 7, 202514 min