Most people will spend about one-third of their life in their bed, so for healthy sleep it's essential to choose the model well - and preferably one that will last for many years. "You don't buy beds in passing or on the internet," says Marc Böhle from the Association of Specialist Bed Shops in Cologne, Germany. "This is one purchase that needs to be well prepared." However, there's a dizzying selection to choose from: single and double beds, family beds, box spring beds, sofa beds, solid wood b