It is around 40 years old. Concrete slab, 2x4 walls on 16 inch centers. 8 or 10 inch roof trusses. It was built mostly by FIL and 2 teenage sons. So yeah well built.
The back wall is almost completely gone. If the insurance company deems 35-40% damage, they will total it. Salvage is his. This could be best for him financially. He could take the funds and repair or rebuild. Then is possible to re-insure.
Similar thing happened with us after Hurricane Floyd in 1999. Total loss sounds bad but sometimes faster and more $$$ for repair.
Crazy world!