As personality types go, the well-heeled bon vivant and the pious preservationist would seem to have little overlap. The guy intent on living with a state-of-the-art surround sound system and an outdoor spa big enough to hold 20 friends is generally not the same sort of person who purchases a dilapidated historic house as fragile as a Ming vase.

But Lyndon Saia is the exception to that rule. He is both of those people. For the past 4½ years, he has funneled profligate sums of money and almost all of his time and attention into the painstaking restoration of one of New Orleans’ neglected treasures: the Old Spanish Custom House at 1300 Moss St., thought by architectural historians to be the oldest surviving residence in the city.