Is roofing a house feasable self help project or better left to pros? ALL DONE!!

[HANDM]

Years of prior neglect has caused the concrete tiles to start deteriorating especially at the moss growing sites.

I'm not replacing the roof just the busted tiles. All of the "feet" were broken on 60 tiles which would have required me to nail all of them in which would screw me if any of them broke later and I had to replace it.

In the picture I am in the process of repairing/ overframing the huge sag that was in the overhang (father in law hack job) which is how all of the tile feet broke in the first place 

Worst part about this house is that I rarely have help maintaining it and it seems that once I finish from one side to the other, I have to start all over again...... I wouldn't have it any other way however.

Good thing my Mopars taught me patience