We built an extension 20 years ago with full planning and applied for business controls. Whilst we had several inspections during the build the final inspection was never done (long story). The council now outsource it to a private company and looking at the website it states that if it was done before 2013 and building controls was applied for then all they can do is issue a letter stating that they will not take any enforcement action. If completed after 2013 they can do a regularisation certificate after inspection. Strangely, if no building controls had been applied for then they could also do a regularisation certificate if completed after 1985. We are planning to sell in about a year so not sure whether to get the letter, contact the council/private company and see if they can do a regularisation (despite what it says on the website) or do nothing and get an indemnity when we sell. As no enforcement is possible after 10 years the indemnity is pointless but it seems to tick a box for mortgage applications. We are going to get a full structural survey including electric and plumbing surveys done ourselves before we sell and declare the situation up front. I wondered if anyone had been in this situation and what you did.