From what I know, ensure the DSG box is smooth and quiet with no lurching when going into first.....the mechatronic units are know to go. £700 to fix. Other than that, usual things as others have said. Belt changes, front wings, usual due diligence checks on panel gaps, paint etc to check for any evidence of poorly repaired damage etc. General appearance should suggest how well its been kept. Tread depth and brand of tyre will also be a good indicator.
Gut instinct is a pretty good radar for cars. It's never usually far wrong. My current daily I bought on, amongst other things, a decent gut feel and the evidence it had been cared for. 75kk in 7 and a half years later and all its needed are a rear bearing, a ball joint and a coil pack......
