Regarding the rates being charged, you are apparently grandfathered as a MHP in a commercial zone: Find what jurisdiction set the rates (municipal supplier); if it is your city, request an exception, which may require a formal hearing in front of the city's judicial board (most likely city council). We have had favorable results.
Also, in our 20+ years in the sub-metering business, we ave often found the commercial rates are lower than the residential rates: In an effort to stimulate commercial development.
When you are ready to move forward, please feel free to contact me.
We’re here to answer your water sub-metering questions.
Southern Water Management