Degraded quality house by Hallmark builder in Hyderabad

Hello Sir/ Madam, I am an unhappy home buyer who invested all the savings to buy a house with Hallmark builders (Hallmark Silvanus) in Hyderabad. During handover we had observed many issues like water seepage, broken tiles in rooms, broken tiles in bathrooms, damaged tiles in bathrooms with white cement, uneven ceiling & uneven walls, uneven wooden flooring, damaged bathroom fittings, rusted window grills, broken sliding door glass. Upon multiple follows ups the defects were worked upon but not resolved completely, as we had to move in because of my kids school we shelled out extra money and got the issues resolved. Even for interiors, we have to give extra money as the ceiling was uneven & we had to use fillers to fill the gaps. Within 6 months, we started observing water leakage from wall, hence had to get the builder to break the tiles of the bathroom to resolve the issue. The internal water pipe in the bathroom was leaking and this damaged the wall. Again in few days saw water seepage from other wall of the bathroom. All this happened within 6 months since we started living in the house. The builder delayed the completion but had given handover to owners partially, the club house they promised is also of low grade construction & water seepage all over the walls and fully functional. Many of the residents are also frustrated but no action is being taken. I would like to make sure the builder is sued for this and he would not cheat future customers with low quality construction. Please advise what could be done from my side. Regards, Ghouse