I reckon that price is ridiculously expensive, nearly E90 money at 17k. I've seen good e90 330i (non Motorsport) for less than 20k
. With those issues I wouldn't budge from your 15k offer, in fact I wouldn't even pay that.
Regarding the issues, it's just common wear and tear, I wouldn't let that put me off a car but it would need to be fixed at the previous owners expense.
This facelift one has done 15k more and is 2002 but it's 10500 before negotiation.
http://www.trademe.co.nz/motors/used-cars/...n-618735405.htm