Are there any practical methods for implementing usage-based billing without submetering?

Since your goal is to build a portfolio of rental properties, you’re right to weigh both the financial and practical aspects of this decision.

From the little I know of law, you are not prevented from speaking with this plaintiff(?)

Simple, the MTM tell them they need to go, I am not certain of PA laws, but I think a 30-day notice is sufficient, and or cash for keys 

I would check state law; in some states, if your property is in an LLC you actually have to have an attorney for the eviction process.

Im sure going after the city would really only be effective in a civil class action law suit where there is enough people and $$$ on board.Over a 6-12k fix, and battling the city alone you'll spend more money and time IMO. 

However they had to have the laws changed in order to operate, which only happened because of a specific set of circumstances involving a huge flood and the owner being friendly with the mayor.

But Schedule C is the way I'm reading the law right now. 

Well you've broken the law by not returning it in the time frame.

Find Brandon's videos on YouTube for the "four square" method of analyzing homes and practice.