Hard disagree here. I have a very high tolerance for bullshit grunt work, and a proclivity for doing things myself instead of spending money, but redoing insulation in an attack is a bridge too far for me. I've done it on previous homes, and it's worked and made the difference I was hoping for, but it was brutal fucking work.

You'll end up spending a whole weekend balancing on your hands and knees on ceiling joists, trying to crawl through a stuffy attic carrying a giant piece of fiberglass, having to position that piece into place, and then repeat that process a hundred times.

It's totally doable to DIY, but if you've got the money this is definitely a task worth outsourcing.