Tina Trahan’s husband had one question when she spent $3.2 million on the “Brady Bunch” house: “Have you lost your mind?”After a two-year campaign she spearheaded, the modest Studio City home used for the exterior shots of the beloved 1970s sitcom has officially been granted Historic-Cultural Monument status by the Los Angeles City Council.But it was an expensive journey to get the house ready for the limelight.