Property Share

Dear Sir, We have 4 flats:- 1) Flat A :- Jointly owned by Myself/My younger Brother and Father. (My name first on agreement) 2) Flat B :- Jointly in My Name and My Mother Name 3) Flat C :- Jointly in My Younger brother name and My Mother Name 4)Flat D :- Jointly in My Father and Mother Name. 5)Village property Now since I have taken the responsibility of clearing the Home loans on flat no A which could be approx. INR 8mn by the time I clear off loan , I have approached that the whole property should not be divided equally 50 : 50 between both of us I should get some extra share due to my contribution in building this properties and family has agreed to this. My question is that since these mostly or specifically like Flat no A B and C are already registered in our names as mentioned above (but of course jointly) what document shall I get executed to get extra share. for example if I want to get Flat no A completely in My name can I get the "Relinquishment deed executed from my father and brother both for their 33.33% share in my favour or shall I ask both to execute gift deed. which is best? Also I would like to know that Flat no B and C are jointly owned as mentioned above with my mother being 50% owner, can my brother legally claim 100% in flat no C or vice versa myself for Flat no B , want to know legality of mothers 50% share in both Flat B and C what will happened, balance 50% anyways we are owners. What document Shall I get executed for Flat no D and village property to have clarity between both of us? [deleted] is my email id