How difficult/expensive is it to replace a left break light? Thanks for your help.

First we need to know year and model, but mst of these cars access the tail light assembly through the trunk. On some there are a couple of wing nuts and the interior cover comes off and then it is remove and replace the bulb.

Hi Bear It is an '01' 740il.

Should be as simple as opening the trunk and seeing if there is a cover over the tail light assembly, if there is there should be a couple of finger style nuts to unscrew and expose the bulb holder. Bulb holders half turn out and the bulb is in plain sight.