A rooftop or terrace of a property comes under a common area and is meant to be accessed by the residents and owners. It has been witnessed that developers try to give access to a terrace or sell it for payment which is considered to be illegal
The common areas are the undivided parts of the commonly owned premises. The areas such as the parking lot, lawns, corridors, lobbies, elevators, etc are not owned by a single individual owner. The responsibility for upkeep and maintenance of these areas is collective.
The tax receipts are not title documents, it is just an evidence for enjoyment of the property under possession.
As far as the development agreement is concerned it is an agreement between the land owner and the developer, the subsequent buyers are no bound by this development agreement.
The subsequent buyers of different flats may have to enter into a sale agreement and get a sale deed on the basis of the conditions mentioned therein.
If the original land owner is aggrieved by any adverse decision of the developer or any other buyer, then he can initiate legal action as per procedures of law in respect of his rights in the property.