Boston Sewer and Water doesn't accept auto pay either - when I asked, they said they are "working on implementing later this spring." 

If it’s been a month and a credit score of 600 is a problem, then your requirements are too stringent for the area.

Each selected new geography was studied to determine if there was opportunity, and then tested slowly, and then implemented one area at a time.

I don't think Jefferson Parish (suburbs of NOLA) does either.Sometime last year, there was talk of implementing a registration/inspection fee of $100/unit per year (though it may have been $200 for 2 years).It was an exceedingly unpopular idea on both sides of the coin (landlords and tenants). 

I have run into unpermitted bedrooms/additions in California where the code enforcement is much more stringent than in Texas, but I haven't dealt with this in Texas.

You will find a lot of folks who want to open four or eight bed facilities, as the licensing requirements for places of that size are less stringent than the larger facilities.

Has anyone actually implemented it with his/her tenants?

You can implement it nearly all phases of life.If you work in any service related industry you often get an earful. 

Implement Terms in the Lease that Protect the LandlordThe Texas Realtors Residential Lease Agreement is commonly used among landlords, however it’s not a catch all agreement for terms that protect the landlord.

While I agree with your point, the people that I've seen who are able to implement this strategy and make a boat load of money are people who have a lot of money already and don't need their properties to cash flow.