Customer in Tulsa said she could hear her hallway wool "creak" when she walked it, and she was right
Pulled the carpet back and found three floor boards rubbing together where the old tack strip nails had worked loose, so I screwed them down and re-stretched the hall, and the noise was gone in about 40 minutes. Now I ask every customer what their floor sounds like, does anyone else check for squeaks before they quote a job?