Tommy Bahama Style Sofa Table - Two selections you are likely to need to make about which particular sofa you end up purchasing are, what material and colour you want the sofa covered in and what size of sofa you need. Probably the kind of material covering along with the colour you have are the biggest and often the most difficult choices to make.
How durable does your sofa demand to be? Is it likely to get grubby from pets, children, food and drink spills? That is certainly a concern, if you are going for a light, plain colour then. Some cloths certainly will wear thin in high contact regions like the arms and can also be rather fine. Therefore the initial choice really is 'set' or 'loose' covers. Perhaps or so that you can alter the whole appearance of the sofa to make cover washing less of a time critical procedure.
There are benefits to some constraints and both choices too. Fixed Covers; with this kind of cover the cloth of the sofa is fixed to the frame and is not designed as their name indicates, to be eliminated. Occasionally the pillows with one of these sofas will have covers which can be removed but you need to assess how they could be cleaned, usually they will be 'dry clean' only. There's generally information supplied with all the sofa about the care of the cloth read it first.
The advantage however of the fixed cover sofa is of course leathers and that there's generally a much bigger selection of cloths accessible from soft velvet type stuff to hard wearing man. The cover that is fixed also lends itself to more shapely layouts as it follows the contours of the frame and pillow formation. High wear and soiling regions like the arm rests can have different covers on them that are washable.