Thanks--your timing is impeccable since we still haven't gotten around to this and I was just working on figuring out exactly which fan to get! We've decided to stick with Panasonic in spite of our bad experience because it is the easiest to fit into the space (same size) and everyone else seems to have good experiences with them, so hopefully ours was just a lemon. Do you have recommendations of specific Panasonics other than the Whisper Fit Lite, though? Our current dead fan is theoretically more than powerful enough for the space (twice what we need based on the linked site) and as far as we know the ducting is good to go (was put in when the fan was four years ago) but we never got very good venting from the first fan. Possibly whatever caused it to die was also he cause of the earlier issues, though.

we used a handyman to do ours. we had an electrician install the fan, but as far as exhausting it--as soon as roof was involved they weren't going to touch it. We are currently in a master bath remodel, they are using the exhaust already in place, but with new ducting, electrician installed the fan, but the GC is doing the ducting. Hope that helps.

Think you missed something, Tom. She doesn't want to vent into the attic. She wants to vent OUTSIDE by punching THROUGH a closed section of the soffit. That section of soffit is 4 feet from any vents. FWIW, it is not the optimal solution but it is extremely common where I live because of heavy snow and ice buildup on roofs which can block roof vents; it does meet code, and it is a hell of a lot better than no fan at all or just venting into the attic as so many nimrods do. Our upstairs bath fan is vented out through the soffit because there was nowhere to go in a side wall due to the angle of the roof, going through the roof would have tripled the cost of the installation, and going through the gable end would have made much too long a duct run for the fan we needed to use. (Long story I will not go into here.) Since our house had continuous soffit vents, the vents for several feet in either direction from the outlet were blocked off so the warm, moist air wouldn't rise back into the soffit. There is a special duct outlet made specifically for going through a soffit, it looks like a short (maybe 6" long) cylindrical pipe with a grille at the end. A hole is cut in the soffit, the outlet pushed through from the outside and glued in place. Then the duct is attached to this. One with a screen inside the grille will keep insects from coming in and taking up residence in your attic. Make sure you use insulated duct so you don't get condensation in the duct (and be careful when you open the box with the insulated duct - it's packaged compressed and ours sprang out like those peanut cans with the "snake" inside!).

During. He can cut the penetration, flash correctly, etc. You will still need the electrician to run electrical for the fan. Cutting the hole in the ceiling and running the ducting is a gray area. Sometimes the electrician will do it. Sometimes the roofer. Sometimes neither. Sometimes you need the HVAC sub for that. Or a handyman. But the better option for the hole in the roof is always the roofer.