Deduction of charges from the rental deposit amount

Hello, Following is the situation and questions, 1) I have been paying say rent amount x to the landlord and sending the trnsaction statement every month. At the end of the year landlord said rent was X+ Rs 500 and he says he has an agreement copy with X+500 but no signatures. Now he is deducting Rs 5500/- for 11 months and it doesn't seem fair to me and my question to him is why didn't you informed me on the first month of new rent amount and why now? What should be done in this case? 2) Same landlord forget to renew the lease which expired in DeC 2018 and I continued same rentuntil April 2019 and in April 2019 landlord said i am renewing the lease from last Dec with 10% increment as per terms and conditions from previous lease and you need to pay the difference from last Dec 2018? This also did not seem fair to me that without tenant's agreement you cannot charge so difference fo 10% and that too retrospectively. I gave the notice to vacant since rent was unusually high and i di not agree for 10%. During seeking the deposit back the landlord deducted the difference amount of 4 months to the tune of Rs 12000/- and seem to me (tenant) has no choice. What is your opinion? Also 3) finally how much one should pay for the painting charges? Thank you so much!