From a distance Potsdamer Platz looks a bit like its old self. Once the central hub of Berlin, before it was turned into a rubble-strewn no-man’s-land divided by the Wall, it is now surrounded by shiny new towers. Get a little closer, however, and it becomes clear that many buildings are just façades painted onto giant hoardings that rise ten stories high between actual office blocks. This subterfuge makes for a far more pleasant view than that provided by vacant lots. It also points to an unusual degree of restraint among developers in Europe’s second-largest property market (by transactions). The commercial-property market in most other parts of the developed world is in deep trouble. Unlike other property busts, this downturn has not been driven by speculative overbuilding but by investors’ overenthusiasm. Commercial property was a popular asset class for much of this decade. Institutional investors who lost a lot of money when the dotcom bubble burst were persuaded that switching from the stockmarket into property would diversify their portfolios and reduce their risk. Cheap finance was plentiful. Investors could indulge in a version of the ‘carry trade-borrowing at a low interest rate to buy buildings and counting on […]