I am opening a pharmacy in phila., pa. The contractor is telling me that I need to construct and additional entry/exit and completely redo the bathroom to make it ADA compliant. Our bath will NOT be open to the public and we will have less than ten employees. If the building is already commercially zoned, why would I have to do these things, especially since two neighboring business have the same building design and they're open for business and have been recently. The zoning has been in effec for at least eight years, so is it possible that it was "grandfathered". Please also include information on how I'd go about verifiying this information?

Optional Information:
philadelphia, Pennsylvania

Already Tried:
calling city L & I, getting advise from other contractors with different answers