Using BMW listed specifications and only using 325 manual with no options:
A manual 325Ci Coupe weights 3197 lbs.
A manual 325i Sedan weights 3219 lbs. 22lbs. more than a coupe.
A manual 325iT Wagon weights 3362 lbs. 143lbs. more than a sedan.
A manual 325Ci Convertible weights 3560 lbs. 198lbs. more than a wagon.
Automatic Transmission adds 88 lbs.