Appears your outstanding issues are one main water meter and high base fees per home.
Regarding only one municipal main meter: The municipal supplier most likely does not want the cost and maintenance of the individual meters at each home; Reading one main meter is far easier than traversing through your MHP reading individual meters.
Municipal water/sewer base rates charged per home or MHP are typically used if municipality is unable to charge for all of the actual water usage; Noting older and larger meters are unable to capture 100% water consumption (yes, as in inaccurate);
Private sub-meters allow 100% pass-through of the municipal charges, along with a reasonable billing fee. Based on our 20+ years of sub-metering, your MHP's Water - Sewer usage will drop 25 to 35%, and you can accurately track water use, leaks, and wastes.
Call me or e-mail me at anytime, We’re here to answer your sub-metering questions.
Southern Water Management cell 727-421-9695