A successful buy sofa bed means finding a good design which is well made; sounds simple. There are many different styles of single sofa beds, but I believe that the first place to start is comfort. The whole point of a sleeper sofa is that it is a sofa and a bed. Equally, there is nothing worse that having a sofa which you are never comfortable on.
If you have a plain dark blue cheap sofa bed, you can spice it up with cushions and throws to create just about any image. Cushions can be used to add texture as well as color to a room. So make sure that when you buy your sofa you leave a little of your budget for the accessories which will create the exact look which you are after.
If you are in a China furniture manufacturer you would probably judge the quality in three ways, look, feel and price. Upholstery fabrics should be thick and durable, but at the same time they should have a soft touch and should be made from natural fibres. When you are choosing, the comfort of the bed is as important as the comfort of the sofa.