Not sure about Fla but here in DE those type things are done on a letter of intent then transferred to an attorney to draw up the legal aspect once the details are ironed out.

There's a belly in the cast iron sewage line that's about 10' long and about 40' from the house causing the sewage to settle and "back fall" a bit. 

This would include things like the shower fixture, any cast iron drains, and potentially even the tub (although I am always tempted to keep the old tubs).

Ironically, many teachers are renters, which will defeat the purpose of the bill. 

Ironically ...

Its not iron clad for every situation or specific to your state, but could be a solid starting point with some good protections.

Is is old galvanized and cast iron piping, old windows, cabinets, bathrooms, furnaces, etc or has it been renovated.

Ironically I just got an email from the water department with my bill for a duplex I own in Cleveland and it was $44.95 and sewer this month was $53.16 (2x 2bed units with 4 tenants total and newer fixtures).  

Ironically, as a building consultant, i would probably provide the same answer regardless of how you answered 1-3 above. 

@Jerry Robinson Ironically enough, my dad's name is Jerry Robinson.