How has the Roylott family's estate changed over the years in the novel, The Adventure of the Speckled Band?

Stoke Moran, the ancestral home of the Roylott family, was once a vast estate boasting many acres and a beautiful mansion. Over the years the irresponsible Roylott heirs have whittled the estate down to a few seedy acres, and the mansion itself has become old and decrepit. In 1883, at the time the story takes place, only one wing of the house is inhabitable. Dr. Grimesby Roylott and his stepdaughters, Helen and Julia, live together in this wing. It is here, in a locked bedroom, that Julia's murder takes place.