The plumbing rough-in was not easy task.  Due to the space constraints, there were some areas that could not be dug with an excavator.  Sometimes you can use trench plates, but we decided to dig the trench with a jackhammer.

Schedule 40 ABS pipes are more common in California over PVC.  They are more resistant to UV rays, and are relatively inexpensive.

Every plumbing trap needs a vent.  Sometimes you can share a vent if they are close enough.