if it needs a new roof, what is left ? this shelter is basically a roof on posts (and you don't want the posts)
rather than spending all the time, efforts, risks, and permits to haul it down the road, I would either 1) dismantle to manageable sections, 2) dismantle completely and salvage what you can to re-purpose, or 3) walk away. Not worth the time and effort. If the intent is to help your neighbour out, then #3 doesn't apply.
All the best, whatever you decide.