Check for clunking over bumps. The control arm bushings (specifically the "tension strut" bushings) wear out every 50,000 miles. Also, look for rust on the rear subframe mounting points (E46 only) and the jacking points.
The 318i sits in a lower insurance group than the 330i or 335i, making it a great choice for younger professionals or families. Final Verdict used bmw 318i
The ride quality is fantastic, but the repair bills can total the car. Buy with a full service history (FSH) only. Check for clunking over bumps