Newbie needs help with coop design

[Dagar]

We have a 5x8 shed in our backyard contained within a 30'long x 12' wide chain link dog run (since the dog(s) sleeps in the house on couch it is never used) So this is the basis of my coop. The roof on the shed needs fixing. The nesting boxes would be inside not jutting out for easy access and there is only one door, no windows. My biggest issue is trying to modify the shed exterior too much because it has old asbestos shingles on it.
Once I pick a plan/idea, start etc...it won't be easy to undo. So I have two options.
Take down the shed (which has outstanding wood in it) and rebuild, or try to modify the current shed....I am not sure which way to go as far as expense/time etc. Hoping someone has had experience with this.

 

[jetdog]

Leave the old shingles on it and go right over it with metal roofing, put a couple of windows and some ventilation, make everything secure and safe, no sense tearing it down when you can modify it to suit your needs.

 

[Dagar]

Thank you Jetdog...
We will work with what we have.