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It can get very ugly. In an obvious falling market a lot of people will wait for more price drop before buying so there really will be very little buyer in the market.
The developer, construction company, RE agents, high leverage house flipper, low down payment home owner will all take a direct hit. Some will cut loss, some will lose job and forced to sell. Some will be foreclosed.
All these will cascade back to the banks as bad debt loss / foreclosure which will hurt the shareholder and staff will be laid off.
Next when a bank take the collateral on a bad loan and sell (this will drive price further down) to recover whatever they can, the reverse of the fractional reserve happens so say 10% reserve will mean the money supply shrink by 10 times the loan amount. Less money supply means falling prices and probably falling wages. Which spiral back to the next wave of home default as the loan payment stays the same while wages drop.
The higher it went up the harder the fall...