For those whose darker needs aren't satisfied by the usual real-estate, this official add-on installs a ruined hideout on the southern coast of Cyrodiil.
Once restored - at a rather pricey 3,400 gold per room - it's a gothic paradise. It comes with a garden of poisonous plants, a coffin to sleep in, and a perpetually snoozing prisoner for thirsting vampires to snack upon. Also, a lunatic lodger who paints with zombie blood can be instructed to sally forth and kill for you, carting back the spoils. But there's no actual quest here, so Mehrunes' Razor remains the better buy.