Discrepancy in calculation of Monthly Maintainence in the Housing Society

I live in a housing society where there are two kinds of houses. 1. Three storeyed flats 2. Independent houses. The method of calculation of Monthly Maintainence Charges (MMC) is on a per sq. feet basis. At the time of construction of the colony the independent houses had just one storey and its area was lesser than those of flats. But now after a decade or so most of the independent house owners have razed the original one storey house and constructed 2 to 4 storey houses over the original land. The issue is that they are still being charged MMC on the basis of the original one storey house that was handed over to them at the time of possession. Whereas today their house stands 2 to 4 storey high whose area is also 2 to 4 times the area of the original house house at the time of possession. he situation is the flat owners are paying a higher MMC than the house owners despite the fact that the latter's house is double or triple the area of the flats. Please advise what legal action can be taken and how this can be resolved through arbitration?