They have to be disposed properly.3) Tenants must have an active phone number at all times and must alert us if the phone number changes.4) If we snake a drain and find diapers, feminine hygiene products, or anything else that shouldn't be in there, the tenant pays. 

The upside is that the Coop is responsible for pipes inside the walls, exterior maintenance, snow, tax payments, snaking drains, etc. 

I bet you can snake the line and clear the obstruction to get things flowing again.

See here: Youtube LinkYou can spend the money on a camera snake, but if your PM saw tree roots coming out with the plumber when the plumber sent the auger in, I'd say that's good enough evidence for me. 

He has to deal with dead bodies, rattle snakes, intruders and prostitutes; while bringing in $600 a week for the house.

It's a modern day equivalent of the wild west...oil, whiskey, gambling, rattle snakes, prostitutes.

I'm on good terms with my buyer so I helped him out and snaked it out only to find out the line needs to be replaced under the driveway.

The machine would apparently do the epoxy liner by being snaked thru the pipes is my understanding. 

Make sure they do video camera snaking. 

A different plumber actually utilized a snake camera to visually check the alignment of the drain system and it was properly built, including the p-trap.