Unlike some other brands (looking at you, Porsche), most older BMWs are still relatively affordable and haven’t seen crazy price increases in the last years. Notable exceptions are the rare and wanted models: 507, M1, and Z8. Nevertheless, there are a few models were prices have bottomed out or have been rising for a time. Should you be interested in owning one of these models, now is probably the time to buy.
E30 3 series
E30 prices have been rising steadily and have surpassed those of its E21 predecessor – which isn’t surprising, as the E30 is (to me at least) the better looking and more refined car. Most wanted are the 325i and the 318iS, with prices for good examples exceeding €15,000. 325i convertibles are even more expensive. The only models that I would still consider affordable are the 316i and 318i four-cylinders. I would instead aim for a 320i, to get a six-cylinder engine at considerably lower prices than the more popular 325i.
Rust is an issue with these cars, and most cheap cars will have rust issues. Originality can be a problem, too, as these were modified a lot when they were still cheap. I expect that prices will continue to rise, but it will be a while before they will be high enough to warrant extensive restorations, so I’d definitely get one in good condition.
E36 3 series
Prices for the E36 have bottomed out and are on the rise. They supply of good original cars is limited, especially in case of the top models (325i and 328i). Many have been modified when they were cheap, and they became popular track tools when E30 prices started to rise. Build quality wasn’t always great (rust is an issue, as is disintegrating interior), so make sure to thoroughly check a candidate. The 325i and 328i are of course the most desirable. The 323i is worthy of consideration, too, as it has a torquey M52B25 2.5l engine. I would avoid the 320i, especially with automatic transmission. If you want to spend less, I’d suggest the 16-valve 318iS/318ti four-cylinder with the 140hp M42 or M44 engine. Most iS sold came in coupé form, the same engine was available in the compact (318ti).
The compact is the bargain here, but since most were sold as 316i, the higher-powered 318ti and 323ti models are becoming scarce. With all E36s, I prefer the look of the earlier models with the thin kidney chrome.
BMW reacted to the rebirth of the roadster (which can be credited to the Mazda MX-5) with the Z3. It was built on the platform of the E36 compact, and hence carries the E36/7 (roadster) and E36/8 (coupé) type identification. The four-cylinder models are pretty cheap right now – I would definitely go for the M44 engine with 140hp. If you want a six-cylinder (starting prices are twice that of the four-cylinder models), the 2.8l is probably the way to go, as the 3.0l is rare and much more expensive.
BMW also built a controversially styled coupé, which was sold less than 18,000 times compared to almost 280,000 roadsters. Combine with the fact that the coupé was sold only with the 2.8l and 3.0l engines, and it should not come as a surprise that these are quite a bit more expensive than the roadsters. Prices for the 3.0l model especially have reached a level where I would rather consider an E46 M3.
The M3 variant of the E46 was a major success for BMW. While it didn’t have much more power than the 3.2l E36 M3, it’s distinctive styling with power bulge, air vents and quad exhausts make it one of BMW’s most recognisable and best-looking cars. Prices bottomed out a couple of years ago and are slowly rising. Here in the Netherlands, prices currently start a bit below €20,000 for cars with higher mileage and/or few options and undesirable colour combinations.
This means that these cars are still relatively accessible, but beware of the following: the SMG gearbox has a reputation of being unreliable, so I would avoid these (many of the cheaper cars are indeed SMG cars). The S54 is a high-performance engine that is sensitive to oil quality and revving too high when cold. It doesn’t have hydraulic lifters, so requires regular manual valve adjustment, as well as road bearing replacement. Beware of cars without service history, as expensive motor revisions might otherwise result.