1. What do you mean by "wrong" battery? Be specific. "Oh the sa said it isnt the right one" isnt.

2. Be careful. The SA is playing with YOUR money. You need to ask "WHEN did each code first occur?" Engine operating hours are OK. Also ask which are active. I sense a major screwing coming up here.

3. Read up on carbon fouling in the 335d forums. THIS IS A MUST. You will see that BMW has a problem and SOME owners are getting screwed...some are getting BMW to cover issues. It will be worth your time, IMO. I think the cleaning is 2-3k.

Do not let them do too much or suck you in too far.

My 2 cents