We're not saying that you should renovate a house just in the off chance that you'll discover a valuable original poster from 1911 (valued at £3,000, or around $4,266) advertising the maiden voyage of the Titanic inside a fake wall. We're just saying that if you were already thinking about renovating a house and you were 50-50 on it, and the house is also in Wales, then maybe you should just go ahead and do it. Now if you'll excuse us, we need to go destroy all our (potentially fake) walls.