Noufal Ambalapurath

I have given contract for work up to 1st floor concrete. 25 percent of the amount given as advance. now work upto 2 rows of basement done. plinth belt yet to do. If I want to quit the contract and give it to some one else. how do I proceed. can anyone advise. should I go legal. 2600 sq ft home include car porch. can anyone provide approximate cost upto basement using laterite red stone 3rd no. for foundation and 2nd for basement. Basement was for 3 stone height rows in some areas and other area gone upto 7 rows additionally note that septik tank and sewerage tank made. but plaster and concrete not done so far.