Settlement of rent dues by developer - redevelopment project

This is with reference to property owned by my father. The building he was residing in previously has been taken over by the respective builder for redevelopment project. He was supposed to start the redevelopment soon but it is almost 8 years now and he has not even commenced the redevelopment giving lame excuses of pending permits and approvals. Aside from this, he is supposed to pay the rental compensation for the residents of the old building to sustain and survive the period of redevelopment which also he has stopped for the past two years amounting to roughly 3.5 lakhs. I would like to know the legal rights and proceedings that can be initiated by my father (resident) so that he not only gets the rental money back (which my father is currently paying out of pocket at age 76) but also the redevelopment starts at the earliest. If during the period of redevelopment, my father chooses to sell his property to the builder, what should be the basis of correct valuation for the property. Kindly advise.