Apartment owners vs Builder problem

Builder has constructed 8 flats while BBMP has approved only 4. He has registered 6 flats to us who are 6 owners. we have done khata bifurcation and transferred khatas of our individual flats to our names. Builder has also constructed an room and an watchman quarters in car parking area against the BBMP plan. Due to which we 6 owners are facing car park shortage and he is demanding 2 car parks for the 2 flats which he currently owns. he has not handed over forms for forming an association either and all orginial docs related to land are with him. 1. what can we do soon about the car park problem? (he has forcefully parked 2 cars now). Seeking police help did not benefit us. 2. Sale deed mentions about that room which is parking space as belonging to builder and having rights over it. But he is currently running an office there which is hampering our security. what can we do? 3. He has not provided certain basic amenities like lift stabilizer, rescue device for lift and so on. how can we claim the money we are spending on all this? 4.how to stop him from registering those 2 unauthorised flats to other unaware citizens?