I am looking to renovate a property which has three bedrooms at present and also what is listed as a box room. The bathroom is a reasonable size, about 8ft X 10ft and I want to change this into a fourth bedroom and turn the boxroom into a bathroom by installing a corner bath , WC , and basin all of which will fit quite comfortably in the room. My question is , when I put it on the market can it be listed as a four bedroom house or does it need some kind of legal document/title deed to say that it was a three but is now a four bed property ?