"Car parking and open terraces are a part of the society's common area. They are not part of the FSI (floor space index) allotted to the developer. Hence, he has no right to charge any money for this space.
The Apartment Act, for instance, specifies common area as the land on which the building is located, and includes halls, stairs, lobbies, stairways, fire escapes, building's entrances and exits, basement, cellars, yards, gardens, parking areas and storage spaces within the premises. "In a recent judgement, the Competition Commission of India, too, pointed out that the parking area cannot be charged for separately and must form a part of the common area and facilities,"
According to Regulation 36 of the Development Control Regulations (1991) for Greater Bombay, whenever a property is developed or redeveloped, parking spaces have to be provided in accordance with the guidelines in the DCR. Before a builder can develop or redevelop a project, he needs to obtain the development permission and a commencement certificate. "To get these approvals, he needs to submit a building plan, which includes the details of the parking spaces provided. If he does not provide these spaces in accordance with the DCR, he will not get these approvals,
The model building bylaws of the Town and Country Planning Organisation, Ministry of Urban Development, Government of India, specifies mandatory parking space for units in a housing development, and so does the National Building Code (NBC) of India."
So, make sure no one takes you for a ride as far as car parking slots go.
Thus the car parking slots or stilt parking are meant for parking alone and not for any commercial or deviated purpose. The aggrieved may agitate and initiate proper legal action.