The dimensions of the E30 really are a revelation. Here is a design that actually shows constraint, seemingly using as little sheet metal as possible. Taught, clean and no-nonsense. The pillars are thin and glass huge for maximum visibility inside and out. The whole thing is about the same size as a 1990s Honda Civic. Except it looks way better and drives a million times better.
Perhaps the next rarest E30 sold in the US after the M3 is the "iX" models that debuted in the late 80s and lasted until around 1991. These had full time permanent all-wheel drive, utilizing an open, all viscous 10-100% limited slip with three differentials. The torque was divided 37:63 with bias to the rear wheels to retain the rwd feel. The rear and center differential use viscous couplings to split torque, while the font was open.
Inside is one of the greatest interiors of all time. An oversized steering wheel, center console angled towards the driver, and simple white-on-black gauges make a statement that this machine means serious driving business. The leather seats are in unusually good shape. The seller says the dash has cracks but everything is functioning and there are no lights on.
Underneath the hood was BMW's venerable straight 6-cylinder that was good for almost 170 horsepower, which really helped propel this small car. What is gained in weight with the iX equipment is forgiven with the added traction.
The seller of this example is the third owner and has racked up 139k miles. They say it is car fax verified and still wears the original paint. Mechanically, they say everything works except the air conditioning, and a bunch of parts have been replaced. They also say it has a chip boost for extra horsepower, which is awesome, except they say 91 Octane fuel must be used, which should probably be used anyways. Since most were sold in foul weather climates were salt was used on roads, they have mostly rusted away, but this one seems to have survived. The seller says there is no rot except around the rear trailer hitch but they are having it repaired.
Available here on craigslist for $5,900.