E90 N55 auto 335i buyers guide / what to check

[yus786]

Going to buy the above tomorrow and was trying to search for things to check but can't quite find much

Not that big of a car guy so simple instructions please!

Done the usual checks, full BMW service history hpi etc

Any knowledgeable members on here that can have a look at it? It's in Kent, I don't mind paying

Apologies if in the wrong forum etc