> I would expect around 50k-60k for a 1000 sq ft roof (not US).
That's about 90 m². Here in Germany [1], if it's just replacing tiles, you're looking at 10k, add 20k for adding heat insulation - and you can get 15-20% back with government assistance from that sum. The only way you reach 50k in costs here is if you have to fix structural issues (e.g. rotting wood due to water ingress, but if you take proper care of your roof you won't need to do that - expected life time for roofs is about 80 years for the tiles and much more to the tune of centuries for the wood framing.
I included the structure because I only know of cases (including my own) where both needed replacing. Centuries for the wood structure is hypothetically possible of course, but only if maintenance is ideal (no water ingress) and without insects. Once there are water issues, they rapidly decay. Retrofitting both new insulation and additional roof loads like solar is also not possible for every old roof structure. The flat roofs somewhat common in 60s and 70s construction also have very short lives and often need to be replaced wholesale after 40-50 years. Despite the reputation, they're not at all cheaper than traditional roofs, at least not when you have to adhere to the current building codes
A bundle of shingles is $50, 3 bundles to cover 100 sq ft is $1.50 sq ft in materials. Figure $1.50/sq ft to demo and dispose of the old roof shingles.
Materials and demo comes out to $3,000, figure $500 for tools and nails, mark it up to $4,500-5,000
Probably (4) people can knock out a 1000sq ft roof in an 8 hour day, call it 40 hours of labor for demo and install.
Surely the labor cost and markup is not $1,000 an hour, that’s what it would have to be for a 1000 sq ft roof to cost $50-60k. $125/hr for 40 hours is $5,000.00
That's about 90 m². Here in Germany [1], if it's just replacing tiles, you're looking at 10k, add 20k for adding heat insulation - and you can get 15-20% back with government assistance from that sum. The only way you reach 50k in costs here is if you have to fix structural issues (e.g. rotting wood due to water ingress, but if you take proper care of your roof you won't need to do that - expected life time for roofs is about 80 years for the tiles and much more to the tune of centuries for the wood framing.
[1] https://www.obi.de/magazin/energiesparen/daemmung/dachdaemmu...