now you've lowered it be careful as the oil sump is the lowest point on the car
as with any bmw the radiators can leak.
you will do rear wheel bearings if you have the car for any real period of time
be aware they rust around the sunroof, boot seal, bottom of the A pillar, and the bit were the battery sits in the boot.
there isn't anything else really they suffer from to much, they are the most reliable car bmw has made yet
also dont get it hot ever...