How to buy a used BMW M car.

Every generation has its own engine, known issues and price band, and choosing between an S55 and an S58, or a pre and post LCI car, changes what you should pay and what you will maintain.

Start with the scored generation guides, and use compare when you are torn between two. It shows the reliability and cost gap as well as the spec sheet.

Before you look at a single listing, know what fails on your target generation and what it costs. Every generation page lists its chronic issues with inspection advice and repair estimates.

If you are shopping S55 cars, read the crank hub guide; if it is a V8 car, the N63 story.

Run the VIN before you drive anywhere. Our Score It tool decodes VINs through NHTSA and scores the exact spec, so you can verify the year and model match the listing and see how the configuration ranks.

Every generation page shows live NHTSA recall data for that platform. Note any open campaigns, then have a BMW dealer run the VIN to confirm completion.

Recall work is free by law for cars first sold within 15 years of the recall, and an ignored recall tells you something about how the car was cared for.

Dates, mileage, shop names. What you want to see:

• oil changed at least as often as BMW's schedule (on recent cars, yearly or about every 10,000 miles), ideally every 5,000 to 7,500 miles and sooner on V8s;
• cooling system work on older cars as normal aging;
• and consistency: one trusted shop beats twelve random ones.

Gaps in history are negotiation items; a total absence on an M car is usually a walk-away.

Records show how the car was kept; a title history shows what happened to it. A one-off report from a provider on the Justice Department's approved list, such as EpicVIN, shows title brands like salvage or flood and reported accidents, for less than a subscription service.

Even briefly, even a prior owner, even "just a JB4 for a month." Tune history changes risk on every turbocharged M engine and specifically drives the S55 crank hub question.

Mods are not automatically bad. Documented work by known shops can be neutral or better; undocumented tuning is priced like the risk it is.

Ask them to check the generation's known issues by name; you have the list from step 2. This is the best money in the entire process.

Everything above converts to numbers:

An unaddressed known issue

is its repair estimate

Missing records

are future resale value

An open recall

is a dealer visit

Worn consumables

are a quote

Buyers who negotiate from documented specifics get better prices than buyers who negotiate from vibes, and sellers of good cars respect it.

Buying out of state? Get transport quotes before you agree a pickup date: Montway books door to door, and uShip collects quotes from many carriers. Enclosed transport costs more and keeps road debris off the paint.