RBI mandates banks to ensure 'reasonable property prices'-how to implement?

While reading the RBI master circular on Housing Finance issued in Jul-11(http://rbidocs.rbi.org.in/rdocs/notification/PDFs/52MC2800611F.pdf), one condition was that banks could extend term loans to builders only for specific projects(no general loans), and not for land acquisition(even as part of project). The subsequent text made my jaw drop.



Care should also be taken to see that prices charged from the ultimate beneficiaries do not include any speculative element, that is, prices should be based only on the documented price of land, the actual cost of construction and a reasonable profit...
 Has anyone even thought about how will the banks enforce this? For a sector without a price regulator, with no accepted costing standards and with so much opaqueness, who will make this work. Let us see each of these 'price elements' which the RBI desires.

1. Documented price of land:- Land transactions involve substantial amount of black money. But accepting the principle that Govt should punish black market deals, this is fine-punishing the builder for undervaluing the land procurement cost.
2. Actual Cost of Construction:- What about overheads, interests, construction delays(avoidable costs) etc? We do have accounting standards for all of them, but they need to be audited, on a project basis,  to be of any use
3. Reasonable profit:- Who determines this? Market(via P/E/ROE/markup) or Govt(price cap etc). This determination is an open invitation to rent seeking.   

Good intentions are fine, but why play to the gallery to mandate something which you know cannot be enforced? This will only give RBI the excuse to point fingers at lending banks, when blamed for rising prices. And at worst, banks may curb term lending and structure it differently. However one slices it, this is just not done.