Illegal wall and violation of other rues by a flat owner in my apartment

I am the resident of an apartment by name Sapthagiri residency at Hyderabad. The plot of 400sq yards was assigned for development to a builder by my father. I have got one flat as gift deed. At he time of construction, the builder had illegally constructed a wall in the common parking area and enabled the groung floor flat owner for his exclusive usage after allegedly receiving a kick back, disallowing others to use the enclosed area. On protesting the builder absconded from the work and left few unfinished works like lift, watch man room etc. After 2 or 3 years the ground floor owner complained of leakage of water from our bath rooms, since my flat is located exactly over his flat in the first floor. Additionally he has refused to cooperate whenever common issues rose and needed monetary contribution, like painting of building, laying of tiles for parking area etc. citing leakage of bath rooms. I have been refusing to get the bath rooms repaired till he pays back all the dues and gets the wall demolished. Am I legally entitled to do such an act ? Now he is threatening to halt paying monthly maintenance amount. Do we have a legal recourse to tackle this problem once for all ?