Second Hand Flat - Builder Delayed the completion for 05 years - Issues in car parking

I have purchased a flat second hand in Chennai. The construction agreement between my seller was made during 2013 and promised to hand over the project within 10 calendar months. However, the builder has delayed the completion of the project till now, after various round of talks by all the owners of the flats nothing fruit full happen as the builders quoted he is financially not in a position to provide the completion (Major portion of the left over work is car parking area development). Since, the builder is not in a position to carry out the work in his capacity, we the owners of the building have contributed money and asked the builder to carry out the work as a outside contractor. After completion of the work, the builder has marked the car parking area on his own wish allotting a worst area to me and even after protest from our side has not agreed to undo his work. Since few of the owners of the flats are friends with the builder, I feel cheated by the builder. What are the legal remedies available to me to stop the builder to do further damage to my interests in the property ? Can sue him in Consumer Forum, Court, etc. for the delays he had caused ?