The BMW 3 Series E46 is often considered by purists to be the pinnacle of the 3 Series in terms of balance between comfort, dynamism, and build quality. Replacing the E36, it was available as a Sedan, Touring (wagon), Coupe, Convertible, and Compact. It underwent a facelift (LCI - Life Cycle Impulse) in late 2001 for the sedan/wagon and in 2003 for the coupe/convertible. While its inline 6-cylinder petrol engines (M52TU and M54) are legendary for their smoothness, the E46 suffers from well-documented chronic weaknesses (cooling, running gear, rear subframe) that require rigorous maintenance. Today, it is a highly sought-after 'youngtimer', but one that requires a significant maintenance budget.
The BMW E46 is a fantastic car that requires a knowledgeable owner. Absolutely prioritize the 6-cylinder petrol engines (320i to 330i), which offer the authentic BMW experience. Avoid the late-production 4-cylinder petrol engines (N42/N46) and un-reliabilized diesels (intake flaps). Buying an E46 today should not be based on mileage, but on service history: a 250,000 km model with new cooling, a reinforced subframe, and revised running gear will be a much better purchase than a 'lemon' of 120,000 km with no invoices. Plan a budget of 1000 to 2000 € post-purchase for preventive reliability upgrades.