The Coupe variant offers a boot space of 440 litres . The Convertible variant has a slightly smaller cargo volume of 385 litres due to the mechanism for the folding roof . For buyers considering the BMW 4 Series, that matters because it affects how easy the car is to live with, whether for commuting, family use, long-distance driving or ownership costs. The useful way to read this is not as an isolated specification, but as a clue to how the car will feel in real daily use.