Hello Pabitra,
If you have booked the aforesaid property for commercial purposes, then you can file a suit in ghaziabad civil court. However, if you have bought the space in question for establishing your own business/trade or any work to earn your livelihood, then you can file a complaint in the consumer forum. I say this because one of my clients has a similar case in NOIDA. He booked an office in Noida, the builder paid the assured returns in the beginning but gradually stopped. Neither he has completed and handed over the office space. We have filed a complaint in district consumer forum and the same has been admitted. We have now been instructed by the cunsumer forum to file evidence. Conclusion, if you have booked the space to earn your livelihood and you are currently dependent upon the assured returns for your livelihood, then you can approach the consumer forum.