Traditionally, the Porsche Boxster has been cheaper than the coupe version, known as the Cayman, but for the 718 generation, they've swapped places. That means you have to pay more if you want open-air thrills, but in fairness, that’s also the case with most other convertibles. The reason behind the huge shift in engine technology from Porsche was to help improve the efficiency of the 718 Boxster, and the results on paper look promising. If you pick the standard Boxster, and then equip it with the optional PDK automatic gearbox, it'll return impressive fuel economy and CO2 emissions, especially when you consider the performance. But in reality, if you drive it hard, this engine will probably be just as thirsty as the old model. When you ease off, though, stick the gearbox in auto and take it easy, that's when you'll notice the added cruising range. Manual versions are cheaper, but also less efficient. Parts, servicing and insurance are all likely to be costlier than the class averages, too, but strong resale values go a long way to offset that.