I've done some roofing in my life but, I learned years ago that there are people who do that for a living!
It may cost me more money for the job but, it is made up for by having the job done right, quicker, with less pain and stress and the possibility of need of medical attention on my body.
Plumbing is another thing that I leave up to the "leak proof" guys with the butt crack showing.
Electrical and a few minor home repairs are about the only things I will even consider anymore.
It is kind of like auto repair. Years ago, I thought nothing of changing the oil, filters, spark plugs and points in an afternoon. Today, not only do spark plugs last for 100,000 miles, I can't even find them on most cars. And as far as oil filters go, finding them on the motor is hard enough but, finding the "RIGHT" filter for your particular motor and year is an exercise in research and asking questions that takes most of the afternoon anyway?
Leave it to someone who knows how, with the correct wrench, and has one in stock!
Rog