I’m not sure you’re correct about the reason the condo projects have stalled. They have stalled bec. the banks don’t want to finance them without knowing the builders can sell them, not because the construction cost exceeds the sales cost. Any time construction cost exceeds sales cost, it’s because the builder overpaid for the land.
The value of a house is cost of land plus cost of construction.
The runup in prices is due to a runup in the cost of land.