Hi Fellas, just researching my next buy as 2007 - BMW 530i in Dubai and prepared a below list of known problems in that year model. I might switch a year or two later to 2005 (older shape) as that year engine was solid and have lesser problems compared to 07.
-> Engine vibration at idle speed caused due to exhaust dampener.
-> Engine valve lifter (Tappet) makes too much noise due to dry running - cured by new engine head.
-> Starter failure (New starter motor is needed).
-> Transmission failure or leaking fluid. (If it leaks new seals, filters and sleeves is needed). If fails - Rebuild.
-> Battery drains out pretty faster due to common battery leak - lead to frequent battery change.
-> Sunroof leaks water during car wash.
-> Minor electrical problems.
-> iDrive module failure.
-> Door beading and seals (squeaking) wear off faster - due to inferior quality (makes noise on highway).
-> Stuck CD in CD player many times.