Before buying a new home, it is very common, and perfectly natural, to have ideas of changes that you might like to make to it. Many of these might be simple cosmetic changes such as redecorating or renewing the bathroom suite. However, if you have bigger ideas for changes that might include physical alterations such as knocking down walls, building extensions or adding new structures in the garden then do seek further advice on these things now before you progress with the purchase. Listed Buildings do not have the luxury of ‘Permitted Development Rights’. Anything that you do beyond basic maintenance and cosmetic repairs will require prior Consent. If your ideas are potential deal-breakers (meaning that if you were not allowed to make those changes then you probably would not choose to buy the property) then it is essential that you engage a skilled Conservation Architect now and book a ‘Pre-App’ meeting with the local planning authority Conservation Officer as soon as possible, and certainly before you exchange contracts for the purchase.
If you know at this early stage that there are things that you want, or need, to physically change then seek further advice now. Do not assume that you will be able to do whatever you want to the property.