• Tenants v/s Landlord and builder

We(the tenants) have been residing in Mumbai since birth, the place where we stay is a chawl. Its a paddi system.
Our Landlord is a builder also.
In 2006 the landlord cum builder has proposed us a plan of a building and most of the tenants had agreed at that time.
The Landlord had made an agreement in 2007 that he would make a building for us (tenants) in the back area of the chawl and would shift us in that. The front portion of the chawl  will be used by the landlord cum builder for commercial purpose. 
So far he hasn't done anything till date (2014).
Now a days the conditions of the chawl  is getting worse day by day. 
Recently we (the tenants) got a notice from BMC and the BMC is considering our premises(chawl) dangerous for resident.
BMC is urging the tenants to vacant the premises 
15-20 days back we(tenants) had a meeting at Add Comm Office  of BMC with the landlord . But the concern person(decision taker) from the landlord was not present there, his servant was representing him(landlord). THE BMC officer told the builder cum landlord to submit the necessary paper for IOD at the earliest and they(BMC) will grant them IOD. (What is IOD).
My only concern is that even if BMC grant them IOD. and after vacating the house the landlord doesn't make any building for us. In that case what we should do. As the agreement was made in 2007 and so far the builder has not taken any action. What assurity is there that the builder will make the building. We(the tenants) are all middle class families. Kindly guide us what we should do in such situation.