Those metal studs didn't know what hit them.
You no longer have a vent for your toilet when you change the elevation
The back flow device needs to be tested and repaired. It is leaking there to let you know it needs service. In my state you would need...
Is the heater electric i presume since you did not mention any gas.
I think they are yanking yer chain. I believe all floor mount toilets have the same outlet to mate to a floor flange. The wax ring may...
Its not code for IPC
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