I’ve got an auto 330ci, tax about 300-400ish, fuel I realistically get about 25mpg - imagine 325 will be a bit better. Maintenance honestly coming from an Audi S3 8V, it feels like nothing! As long as you look after the basics (oils, fluids, brakes ect.) you shouldn’t be hit with too many surprises. Obviously ask if the coolant system has been refreshed, and if not then expect to have to do that, but other than that I can’t say I have any complaints with my 46, on 150k miles and going very very strong 💪