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Run last 7 of VIN at bmwvin.com to see all options and production date, but get in-service date from dealer for warranty and CPO expiration. If you don't know the package and option codes, go to
http://************/97ntw7u for 2011 coupe option info. Run the Carfax and Autocheck (but don't rely solely on those).
Have the dealer black out the prior owner(s) names on the DCS and send you the DCS (service, etc.) history in advance. If it checks out, offer $60k or just under and go from there.
Good luck.