It looks like we paid around $4000 for insulating the crawl space, attic, and all walls (interior and exterior). We do have to have a drywaller come and patch the holes so I can repaint, which will be more money. So far though, I am pleased. We already have newer windows and solid doors, so the house is pretty quiet. I think I had hoped that the interior wall insulation would do a better job than it does on attenuating sound, but it is still nice. The best part is how the house stays almost the same temperature now instead of getting darned cold at night and uncomfortably hot in the afternoon on a warm day.