1. The builder is cheating you by mentioning the non-existent rule or law in this regard.
Actually the builder cannot sell the car parking as a separate unit.
It is the duty of the builder to provide car parking space to the apartments/flats of the complex.
If at all you are purchasing a new property and intend to negotiate with the builder then you must know that a builder is not authorized to sell parking spaces as individual real estate units.
According to the “Apartment Act” in most states, car parking is a part of the society’s common areas. Since the purchase of parking slots has been deemed illegal, the transaction to purchase would become null and void. Once the housing society is registered, it becomes the owner of all the common spaces of the apartment complex including the parking spots.
2. The builder cannot force the buyer to buy the car parking space too.
3. You can refuse and ask him to produce the said relevant rules before you which makes it compulsory to buy the parking space separately