Community Electric communicated exceptionally well about the project. The estimator realized after the visit that he had forgotten to check the direction of ceiling joists and immediately called me. We agreed that placing the fan in the ceiling might be tricky, and the installer and I eventually agreed on a wall fan with ducting existing through an exterior wall rather than the ceiling. (Flat membrane roof, no joist gaps, etc.) The different fan increased the cost somewhat but the solution was much preferable to and cheaper than penetrating the membrane and bringing a roofing company into the equation.
All work was completed in about five hours, which included trips to pick up the different fan and some hanger brackets for the new duct. Running the wiring required making several holes in the drywall. The installer plugged the holes neatly, and I spackled, textured, and painted the surfaces. Easy.
All in all, a very nice installation job handled by very attentive and courteous people from Community Electric