That’s probably a good estimate for an average home in this area, but it really depends on the build quality. I’ve seen high end homes at well over $1,200/sqft.
I think a big unknown factor right now is how the demand surge will impact things. There are only so many home builders in the area and they are not equipped to deal with this kind of volume. It’s going to be hard to get skilled workers and access to construction materials when everyone wants it all in the same place at the same time.
Many good insurance companies pre-negotiate rates for labor and pay for building materials to be stockpiled so that they don’t have to deal with as much demand surge, but I’m not sure how that will work out in this case because the scale of the loss is just so big and so concentrated in a single area. There’s definitely potential for costs to snowball.