How much does a fender bender affect a price

A simple fender replacement should not affect the price. Structural damage might.

as long as it hasn't been delcared a total and issued a 'salvaged' title, it's gonna be okay.

I wish I could agree with the other two answers however in my experience this can quite possibly be an "it could go either way" scenario ... I'll explain. With BMW (especialy), depending on the buyer and they are knowledgable the first thing thaey are going to do is check the paint, either visualy or with a guage (more likely a dealer will do this) The reason is that far too many BMW's out there were being (partialy) repainted as part of normal reconditioning when the vehicles came back off lease returns. Problem being that many times the repaint wouldn't quite match or was too thin (most common) resulting in peeling later on. With resale values being strong for BMW right now, consumers are being very careful (and picky) when it comes to buying a used Bimmer. The good news is if you had the work done right and you get the right buyer you shouldn't have any problems and if it cost you less than $3000.00 to repair, you don't have to disclose it anyway but beware of the buyer wielding a paint guage, that's the person thats going to cost you money on resale.. best of luck!

part it out, if you've got the space and the time to sell it one piece at a time---johnny cash