Landlord Giving Notice for Eviction

Hi, My parents bought this residential property in South Mumbai in Nov 1997 through the old paghdi system. Back then they paid the landlord around 21 Lacs & in addtition promised to pay monthly rent of 450 INR through a legal agreement. We currently reside in this property & are the only tenant since its just a 1 floor building with one flat. Over the past 17 years the structure of property had deteriorated and became very weak though landlord kept increasing rent over this period which finally came to 1400 INR/ month currently. Even after repeated requests to landlord he was not repairing the property. Thus finally we had to pay for repairs of his property which we did in Sep 2011. From then onwards he stopped taking rent from us. Prior to Sep 2011 all our rent dues are paid. Then in March 2014 we sent him a cheque of 33,600 INR through registered post for rent from Sep 2011 to Aug 2013 (2 years) since he was not coming to collect from us. However he has not deposited this cheque into his account till date. Finally yesterday, he has sent notice through a lawyer stating of illegal repairs & unpaid rent from Sep 2011 till date (40 months). On these issues he is asking us for eviction or legal action. As mentioned earlier we had already given him a cheque of rent till Aug 2013 & are ready for making further payments of rent immediately. Also we have not done any illegal repairs & whatever changes we have done were authorized by him back 1997 for which he had given us written permission. Hence does he have a right to evict us? How should we respond?