A big part of the satisfaction factor is knowing the $$ savings I'm getting. I was quoted over $15K for this interior insulating and finish work from a reputable pro contractor who does this stuff all the time. I am going to be at about HALF that cost when I'm done, PLUS I spray foamed to stop air penetration that the contractor wouldn't have done. So should be a much tighter building when I'm finished.
Of course the contractor would have had it done much faster than I have been able to do, so there's that trade off too. But yeah, as much as it wears me out daily working in this heat and humidity, there is a nice sense of satisfaction and knowing HOW the job was done.