Even before the Regency, house renovation was becoming quite the thing. Horace Walpole took a nondescript cottage and redid it from the ground up to make it into the Gothic Revival villa Strawberry Hill. Some time after him, the first Duke of Northumberland renovated Syon House, but couldn’t finish because he ran out of money. You’d never be able to tell to look at it (yes, I’ve visited it; it’s lovely).