Breach of house contract

Hi All I entered into an agreement with my contractor for constructing my house in the month of June 2015. It was clearly mentioned in the agreement that the contractor will construct the house before 31-july-2016 (14 months from the date of agreement) for a total value of 55 lacs. The contractors responsibility was to buy the materials and arrange for labor both. However contractor took 90% of the money 50 lacs in Febraury 2016 and remaining 10% of money by July 2016 and agreed to complete the house as per deadline. However he has still not completed the house. As of now only 95% of the house is complete Another 2.5 lacs of work is pending. The contractor now says that the quotation that he gave was wrong and says that he has additionally spent 6 lacs on his own inspite of which the house is still incomplete. So he says won't be bearing any more money and is saying me ( owner )/to add extra money and get the work done. So if that was the case, As a owner I requested him to submit the documents that point to purchase of materials to my house against my payment so that we can verify what he is saying. He then said he will give documents but I need to pay his income tax because that had attracted income tax since payments were made using NEFT. There is no clause in the agreement that says I need to pay his income tax while there is clear clause in the agreement which says the money can be given to him in the form of cash or through online banking means such as NEFT etc. After reaching out to the local police station and getting him connected through them he got his lawyer to talk to me. His lawyer looked at the payments that I ( owner) made and understood the details and suggested an amicable solution where he asked the contractor to pay another 2lacs and asked me to adjust for another 50k. Since it was my house I agreed to this suggestion. However after the discussion is over the contractor is again saying that he will not agree to the lawyers amicable suggestion and he will only pay 1 lacs . I have given him time till June 30 to make the remaining payment and has floated an email as well to which he has not replied. Also he is so adamant and is not willing to show me the payments against purchase of materials. He is orally telling me that he has paid extra again and again. I contacted some legal experts and they suggested that taking to court may not give you verdict soon. It may take years together for this to happen and lawyers will delay it somehow so that the complainant gives up by being fed up. My question is how to get justice.