Sale of Parking space which is registered in separate sale deed

I am a part of the local committee of the resident welfare association in Kolkata. We have a scenario in our apartment whereby one of the owners of the flat who also owns a parking space (separately registered ) has decoupled the flat and parking space and has sold the flat already and is searching for a buyer for the parking space. So my questions are as follows 1. What does the law suggest about parking space – Is it a right over the land or just allowance of parking the car? 2. Should the parking space be considered as a common space where all flat owners have equal rights of the share of land? 3. Can this parking space be owned by any outsider – somebody who does not have any flat? 4. Can a flat owner sell the parking space separately to anyone like somebody who is not owning any flat? 5. If any flat owner who has sold off his flat alone (decoupled from the parking space), can he continue to own the parking space alone? If no, what would be the suggested course of action for such a case? 6. Suggested course of action for Resident welfare committee to thwart any attempt by the ex-owner of the flat to sell his parking space to any outsider. The supreme court judgement was in the light of builder vs buyers , will the same logic apply to owners as well?