Karnataka societies registration Act 1960 - Apartment Maintenance collection

Hi, I stay in an apartment which has 73 flats which is a combination of 2BHK and 3 BHK. There are 43 - 2BHK houses of varied size starting from 950sq ft to 1100sq ft. The 30 3BHK houses start from 1200sq ft to 1800sqft. The apartment association was formed last year under "Karnataka societies Registration Act 1960". The committee members have made a decision to charge maintenance by sq ft of Rs 3 per month. So, we now have s scenario where 2 BHK owner may pay Rs. 34200 as maintenance while a 3BHK owner has to pay Rs. 64800. As i understand maintenance is collected to maintain the commonly used facilities like lift, gym, pay area , security or swimming pool. 1. is it legally correct to charge maintenance of per sq ft basis? 2. As 2 BHK owners are more, can they pass make a by-law to make the sq ft calculation correct and enforceable. Can the association make a by law and by passing a resolution is AGM and force us to pay by sq ft? 3. Is there any previous court rulings which give guidance on this topic?