Nice s trap made there I'd cut that tee out put a whe in there and studer vent gotta have a vent and I would try and have two traps one for disposal and one for other part of sink
Caduceus if I live in one of those units I wouldn't let anyone tie onto my line cause if this one goes now other tenant I'm sure isn't gonna share cost
When you are trying to snake drain put cable in slowly and use a light and make sure it goes down actually watch cable it will take a couple times you will get it
Hello everyone my name is bob from Pittsburgh pa new to forum aim a journeyman plumber in allegeny co Pittsburgh have 7 years exp in field doing service again just wanted to say hello