It gets expensive as well, I know of someone that was fined £10,000.00 for putting a screw into a listed plaster panel within a building.

As he had deliberately ignored the conservation officer the fine was multiplied by the number of screws he had used - totalled £80k & could have been 2 years imprisonment if the damage he had done was more serious.

I have also worked with an extremely rich client that turned rather pale when we quoted £8million just to reinstate his manor house to how it should be after a conservation officer spotted some unauthorised changes.