Unless you are going to file some kind of discrimination suit against the bank based on what you feel is arbitrary denial, banks do not have to grant everyone a loan just because they qualify - they just can't deny you a loan based on one of the protected classes (religion, race, etc).

Claims I am abusing the forums and rules. 

You need to contact a real estate attorney who performs litigation and not just a contract and "book" Attorney.They will have private investigators who will track down and investigate the property management and interview the tenants.You may have a bit more problems than you know about,yet.This won't be cheap but you have got to protect your property and investments from fraud and abuse.

I signed up online for water service, but was denied because apparently I need a master meter, which requires almost as much documentation as purchasing the property itself!

Many people like to deny it but I feel that unfortunately it is the truth.

So far, we have not had an issue with abuse, but as @Neil Metzger mentioned, that is always a possibility.  

Ideally, I'd like to be able to change the rules moving forward right now since we have a vacant unit that we are renovating, but I don't want to remove an otherwise good and paying tenant to do so before they are ready to leave.I had wondered about what @Johann Jells had mentioned, but I wasn't able to find anything in our Landlord/Tenant laws to either confirm or deny it.  

There were abuse by unscrupulous REI and the NCGS put in writing the minimum standard for a 'legal' CFD transaction. 

I just tried to get financing on a commercial property with a 3:1 DSCR and was denied because my global DTI was greater than the bank's requirements.

What will happen is the adjudicator will order the tenants to pay rent and deny the eviction if one or both of the tenants wish to stay.