My experience of driving my Z3 (top opened) passing a narrow street was that I noticed that some Africians tourists sort of trying to jump out from a van parked over the pedestrian street. Just as I was driving on I heard a big 'bang' and my Z3's whole damn side mirror disappeared ! When I stopped over and also found a big scratch over the door. And all that costed me $800 to replace and repaint. The van driver did not know what had happened and it was that his friends pushed the front door wide opened and hit on my car. We did argue a while and later on I knew I had to give up this time ( as I had been winning two court cases for the last two incidents on my E320 Benz ).
Lesson learn - avoid situations like these by using the horn !