SARASOTA, Fla. — After Vinny and Julie Ciulla bought the “Umbrella House” in 2005, fans of famed mid-century-modern architect Paul Rudolph started knocking on their door asking to see the inside.

“That was a little inconvenient, so we decided to give tours,” said Vinny, who with his wife has spent more than four decades designing museum exhibitions across the country. Since they opened their home for private visits, dozens of architects, students, and the curious have been treated to up-close views of the 1953 cube house. Hundreds more drive by, many stepping from their cars to snap photos.