Where can I lodge complaint against the builder who build the house 174sqm lesser than the contract size and demand Rs 4 lakhs more than the contracted amount . He also denied access even to see the house by our parents, locked the house. Construction not complete 7 months after the contract period.
As it appears from You problem that it was contract of construction by builder, You can approach the Consumer Forum against the builder as it amounts breach of service obligation on the part of builder.
Consumer forum is cheap and comparatively quick remedy. You can compel the builder to strictly comply the terms and conditions of contract and can also seek inspection of premises. You have to immediately approach the Consumer Forum of Your Area through good local advocate. Delay will affect your rights.
You have to take legal resorts against such builders immediately, You can also file criminal complaint of cheating and fraud against the builder.