Leave it to Ken Fulk to transform one of San Francisco’s “finest houses” without losing any of its period drama. One evening a few years ago, San Francisco designer Ken Fulk happened to hear at a dinner party that one of the city’s finest houses was for sale. The very next morning, he dropped by, “just for a look,” and in a heartbeat, he was on the phone to longtime clients with three grown children, who were on vacation. “I think I might be standing in your new house,” he announced. But then he told them about all the suitors panting for this exceptional Gilded Age, quasi-Jacobean landmark that overlooks the Presidio.