from my experience, valuation is only done after offer letter is issued. their margin in the offer letter will be based on s&p price or valuation, whichever is lower.

unless of course your property is grossly overvalued from the start, then the bank will be suspicious.

demand and supply will determine the price of houses, not cost. some developers have to build, because that is their source of income. if they dont build, they dont have money to pay their staff, to settle their borrowings etc. as such, they must keep to their plan.

some developers abandon their projects because or bad budgeting. some abandon their projects because of sudden surges in the cost of materials.
some abandon their projects because they have siphoned all the money out of the company, and they cant pay their contractors.

also, don't get too excited about the blr being maintained. i think it is just a matter of time before they are forced to increase it. spending is still high.

why don't they just go to the toilet? you would think that investors would know better...