We are about to exchange on a house. We have been provided with all the planning permission and sign off for a large extension on the back of the house. However there is also a small extension at the front of the house. This is a single story extension to the hall and dining room, approximately 3m wide and 1.5-2m depth. It was built before the current owners and we have been told it is around 17 years old, and we have no planning permission docs or anything. The solicitors say that due to the age they don't need to pursue anything as it's too old to be caught out for planning permission and due to the size it may not have even needed it. I was fine with this but am now worried we are missing something? Is this a problem?