This thing:
Looked immaculate but holy shit was it a Friday afternoon car... I bought through a dealer, paying a little more for the privilege and thinking it would give me some recourse in the event of any issues. On the drive home things immediately weren't right...
Headlight beams were wildly mis-aligned despite a clean MOT pass a week before I bought it (I test drove it in the day so couldn't check headlights). The fact this wasn't sorted as a matter or course during the prep for sale was concerning, it also meant I immediately suspected the MOT wasn't legit either. Only one key on collection despite being advertised and sold with two; dealer promised to send the second key on 'when they found it'. The EML came on 30 mins into the journey home too. Not an auspicious start.
I sorted the headlights and took it to the guy I use for servicing etc and got him to give it a thorough going over. Biggest issue was a serious leak on the rear main seal which is a 'gearbox out' job and a full day's labour at least. After badgering the dealer they eventually agreed to sort it through a local garage of their choosing. Five weeks later and still no key I pressed the issue and they coughed for a new key from BMW.
Other things I subsequently found wrong within 5,000 miles and paid to rectify:
1) Driver's seat heating not working on the backrest - only the base worked. Fortunately labour-only to sort as the connector lead that linked the backrest had been severed - reconnected and the backrest heating worked again.
2) Headlamp wash not working (like lamp alignment, this is an MOT fail point; more confirmation it was a dodgy MOT and would HAVE to be fixed for a proper MOT). This was expensive; new headlight washer pump, replaced all the pipework and both telescopic arms.
3) The E46 is known for a fairly unreliable coolant system. Mine was evidently no different - coolant loss meant a new expansion tank, thermostat, housing and top pipes. Also replaced the auto-box thermostat whilst I was at it.
4) The car started hesitating and stalling. Not good. Replaced the fuel filter, camshaft position sensors and O2 sensors.
5) Water pump pissed itself so had a new one fitted, along with the drive belt.
All in I spent over £1,500 on repairs within 14 months. Having paid £5,200 for it, I sold it for £3,750 once I could say hand-on-heart it had been running OK for 8 weeks. I was also open with the buyer all the work I'd had done. Total hit in just over a year was about £3k.
I don't think I was unreasonable in expectations but having paid at the top end for it and after being assured by the dealer it was 'one of the best they'd seen' etc etc I felt justified in holding them to sorting the rear main seal under their warranty and supplying the number of keys they said they would. The rest I sorted out of pocket so I don't think I was 'one of those' customers.
I'd always loved the E46 coupé shape - I couldn't justify an M3 so the 330Ci was my compromise. However to say I was happy to see the back of that one is an understatement. It's still MOT'd and has a further 10k miles on it since I sold it so hopefully it's behaved itself better for the guy who bought it than it did for me...