Tub drain problem

[Lemmy]

View attachment 57961 https://www.co.lincoln.or.us/sites/..._-_helpful_hints_residential_construction.pdf

I commented on the picture. I'm not a plumber and this is what I see that is wrong or just not there. The three inch drain was it original? I see no primer at the joints (some are clear in color) and looks like a clean install except some needed support straps. There is one on the left. As I read elsewhere and in codes, the toilet must have it's own vent before other fixtures can drain into the main. This maybe different in your local jurisdiction. Perhaps other can comment on it.

The leak at the shower trap is the slip nut is not on tight enough or the washer for it is kinked or there is none. It would also leak while it is in use. These remodeling guys were not plumbers. Too many couplings between the traps and tees, there shouldn’t be any couplings as good practice in this layout, primer slopped all over the place.

Did these guys touch any electric?

Thanks,

The toilet is coming from 2 floors above and I am pretty sure it is vented there.

The three inch line was all original. As is the vent line. Everything else is new.

There isn't a washer at the outlet of the trap. It is one of these:

https://www.homedepot.com/p/NIBCO-2-in-PVC-DWV-Hub-x-Hub-P-Trap-Fitting-C4885HD2/100342868

and it comes with a 90 that has a tapered sealing surface. I think of it is a "swivel" joint, but I was not sure what it is really called. I have tried to tighten it even with a large wrench and it didn't help. I took it apart and it doesn't appear to be cracked or have any dirt on the sealing surface.

This contractor did do some electrical, but thankfully it was by a different guy that was a licensed electrician. Pretty much everything these pretend plumbers touched is needing some touch up work.