Apartment oriented regarding maintanence

Dear sir Our apt in chennai has two blocks (D1&D2) 2400 sq ft each. D1 has 5 houses( 3 2Bhk, 2 3bhk) and D2 has 6 houses(4 2bhk, 2 1bhk).. Blocks are interconnected thru common stair case, 1 lift. Each block has seperate sewage , seperate motor and borewell. Earlier all 11 houses were paying 1000rs for maintaince which was collected common but due later due to issues, maintenance was split across both blocks and expenses were shared mutually. For eg, if maid salary was 2000, it was 1000 from d1 and D2. This was the case for all including eb bill,lift etc. Now there is a conflict that D2 has 6 houses, D1 (5 house)has opposed that equal split can't happen. Hence D2 block residents have decided on 6:5 ratio for EB bill and lift. But however D1 are claiming for other aspects such as motor/borewell too for 6:5 sharing and not agree for equal. D2 concern is if D1 has separate motor, why shuld expenses be shared for motor, borewll or sewage which is separate for both blks, request ur vie