Guide before you buy
The aim of this section is to get you familiar with the different element you will have to look at when buying a Z3, in order to avoid bad surprises.

Basic Z3 knowledge
Before buying, you might consider the information from this page, in order to be ready when you will be in front of the car.

General
The Z3 is now an old car. The first was produced in 1995 and the last in 2002, meaning that the most recent is soon 20 years old, and the oldest is +25 years old. Therefore, keep in mind that even if the car was well taken care of, you might have some issues with it, even if the Z3 is a reliable car. However, most of those will be fairly easy to solve.

The first advice is to get familiar with different models and variants. It is very common to see a seller trying to sell you a Z3 with an "M pack", when this never existed originally for the Z3 as such. Also, lots of sellers will tell you that the car is "BMW Individual" when it's not. Check optional extras, and refer to the specific categories from this website ("Special versions")

The best thing you can do is ask the seller for the last 7 digits of the VIN number (usually 2 letter followed by 5 numbers, e.g. LJ24507), and check the original extras list from the internet (e.g. BMW VIN DECODER). With this you'll be able to find all information related to extras, color, production date, etc... that will all helkp you to verify if the seller's speech.
Last produced Z3 (07/2002)


BMW M DECODER
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Mechanics and reliability
The normally aspirated straight six are still to date considered to be the most reliable BMW engines, specially the 2.8 and 3.0. If you buy a Z3, this will likely be the part of the car that will give you less problems. Four cilinders Z3 are also very reliable. Both engine types can easily go above 300.000km if maintance has been done regularly. ///M engines are a bit more delicate, with some having Vanos problems (S50 321hp) or rod bearing problems ( S54 3215hp, same as the early M3 e46 units). In case of failure those are expensive fixes.

The chassis is a weak point of the Z3. The front end came from the E36 and the rear end came from the E30. The E30, Z3 and E36 compact share the same rear end suspension, which is not multilink unlike the E36, E46 and Z4. Suspension braces, brakes, steering precision, are all things to be looked at. You may want to elevate the car and have a look under it with a mechanic.
The 3.0i engine won best engine in 2001 and 2002. BMW won 15 best engine prizes between 1999 and 2003.


Body vs. wrecked car?
The Z3 body has some very delicate body parts, and some massive body elements that make its unique design (such as the bonnet). As a general rule, it is quite easy to change a bumper, however if the bonnet, doors or wings get damaged, their wavy shapes will make them hard to fix. But then of course, you can always try to find them on a srap yard.

A key point to look at is the alignment of the body, and the gaps between each part. Non-aligned body panels may be the consequence of a wreck, or a paint job that was not done properly. The bonnet is the most difficul part to repair and re-install perfectly. It is very difficult to get it perfectly aligned to front side wings, front lights, and front bumper, all together. The best solution is still to ask the seller about any accident if you spot something, and just look at his/her reaction...
Body panel alignments
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Interior condition
Even if you buy a Z3 that was fully loaded with extras when it was produced, it is obviously still very basic compared to today's cars.

That said, and even though the leather quality could be better, it is still much better than many cars from today, even BMW ones. I have seen Z3's with 100.000km with much, much better leather than more recent BMW's (e.g. last Z4, e90...) with 50.000km. A z3 with 100.000km should have leather in a good condition, see pictures.
But of course this is theory, as it will also depend on the previous owner. The car can have had an (illegally) lowered mileage, of simply not have been taken car of. In any case, you must be careful when buying.

As a conclusion, a car with 100.000km must have an interior in good condition. If not, you need to be careful. It's either that the previous owner was not careufl, or that he lowered the mileage. In any case, pay close attention.
Some of my Z3's as example:
2.2 with 123.000km - M with 138.000km - 3.0 with 102.000km
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