2. File a Complaint in Consumer Court: If the delay is unreasonable and amounts to deficiency in service, you can file a complaint in the Consumer Forum under the Consumer Protection Act. You can claim refund, possession, compensation or interest on the amount paid.
3. Approach Real Estate Regulatory Authority (RERA): RERA has been established to handle grievances related to real estate matters. In case of delay or non-delivery, one can file a complaint directly with RERA. RERA has power to penalize developers in case they default on commitments made.
4. File a Civil Suit: You can file a civil suit for breach of contract for recovery of amount paid and compensation for the loss suffered due to non-completion of project.
Remember, it is critical to keep a record of all communications with your builder and save all relevant documents to support your claim. Also, legal procedures can be lengthy and may require professional legal advice.