2112 wrote:
The professionals will keep you alive and healthy.
Is the insulation you intend to spray in approved for human habitat? I would hate to hear 10 yrs down the road you have tumors or a respiratory ailment from it.
China drywall comes to mind.
I'm going with this answer. I can learn things that don't have the potential to kill me or learn under direct guidance of an electrician for basic stuff.
I'm pretty handy, can fix most things in my house, remodel, etc. But when I get past wiring a receptacle, installing a ceiling fan, or changing a breaker in a box it's time to call the pro. Knowing how to run romex does make me a qualified electrician.
And good questions you pose above.