The Concurrent List or List-III(Seventh Schedule) is a list of 52 items given in the seventh schedule to the Constitution of India. It includes the power to be considered by both the central and state government. The legislative section is divided into three lists: Union list, state list and Concurrent
The builder is at fault, however if there is no legal document that he has signed to say that he would complete the work and help them, then he isn’t liable.