The driver side door on my R53 doesn't quite line up (see picture below). The car hasn't been in any accidents as far as I can tell (Carfax, visual inspection). Any suggestions on how to fix?

 

How long have you owned the car? I would take it to a reputable body shop and ask them to check it out and give you an estimate. It is free and you would find out pretty quickly if the "problem" was accident related or an easy adjustment. If you bought the car recently and it has been in an accident you would want to know so you could contact the seller.

 

Problem solved. I was a little bothered by a somewhat weak seal at the driver-side window, so I was searching for solutions to that problem. Someone suggested making a slight adjustment to the metal catch on the door. I went out and looked at mine and lo-and-behold it was a little loose, which had allowed it to pull "outside" a little (as in further away from the body). Loosened the bolts a little, pushed it back closer to the "inside" and now the door lines up perfectly.