Property prices are spiralling upwards. Is it still sensible, against such a backdrop, to buy? An investor friend of mine recently told me that he has just sold an apartment building in Berlin for 50% more than he had paid for it, at a price-to-rent ratio of 37. And this wasn't a luxury property he was talking about, neither was it in excellent condition or in a prime location, it was nothing more than a decidedly average, 1970s apartment building.