The most recent guests included mental patients and the sadistic doctor who used the them to perform several awful "procedures." This was in 1922 until 1968. He was said to have committed suicide by throwing himself from the building's tower thanks to being driven insane by the thousands of ghosts who haunt the island. Since then, the island has been highly restricted and only a select few, including the Travel Channel's "Ghost Adventures" crew, have been allowed onto the island.
According to Telegraph UK, "A spokeswoman for Italy’s state sales agency declined to put a possible price on Poveglia but noted that barracks buildings had previously been sold for up to €3.8 million. Another 148 properties are due to be auctioned off this year, with the state hoping to raise €500 million."
We think it would make a lovely hotel and resort destination, don't you?