With major structural damage like this was $100,000 per unit does not seem unreasonable!! Once the building is up I would imagine it becomes far more difficult to repair this kind of damage to make the building stable!!!
There was a condo unit in San Francisco that had this problem on a MAJOR scale owners just moved out and sued the developer who of course filed bankruptcy!! I think the building is still there no one living in it and it is only 10 years old!! Looks like all who purchased their condos are just SCREWED however during the building process I am wondering IF the building inspectors can be responsible for signing off!!
In some states a home owner can walk away from a mortgage and the lender has no recourse to collect from the borrower.
This happened a lot int the State of Washington during the real estate bubble burst. Many of those who stopped paying their mortgages were asked by the lenders to just pay the utilities and property taxes in exchange for taking care of the property.