After weeks of surveillance, the Home Depot security officers knew they were onto something big, but they didn’t quite know how big. They didn’t know that the events of that day would unleash a bizarre yearlong investigation that will culminate in Oakland next week with the beginning of the sentencing process for Davenport, Hay, and Broderick on federal charges of conspiracy to commit wire fraud. They didn’t know that the trio’s trail would lead through at least 24 states, and that the investigation’s nationwide scope would draw in the FBI and the US Attorney’s Office. They didn’t know that the dent the three managed to make in Home Depot’s pocketbook, originally estimated at $400,000, would soar toward an estimated $1 million.