We buy the cabinet hardware in bulk on Amazon and do flush mount hinges, new handles and knobs.

I own one and use it from time to time, @Kevin S.The base of the Nix sits flush against the painted surface, and it has it's own internal light source.

Such as unplugging smoke detectors, flushing things down toilet not meant for the toilet, etc...

I had tenants that stopped paying rent for 2 years in NY during the pandemic and we couldn't kick them out, i've had tenants move out and leave someone squatting and NY made it impossible to evict them so I had to pay them off, i've had tenants destroy their apartments before they moved out (maggots in the fridge, flushing their kids toys down the toilet etc) so i've dealt with real difficulty.

. #1 is probably flushing "flushabe wipes" and female products. 

This is the simplest method, but it also means your tenants are more likely to abuse the utilities by leaving windows open with the heat or A/C running, leaving lights on, ignoring the toilet that constantly flushes on its own, etc.3.

Is it better to flush, or place in a basket next to the toilet? 

But like you have been saying if you feel wronged ( because its apparent you did not understand what you were investing in) your complaints to the regulators will flush this all out..

Decide how much money you would willingly flush down the toilet. 

The most common reason for a high water bill is a toilet that constantly runs or flushes.