The old shitty clay lines are what you find in most rentals in SoCal. Then one day none of your toilets flushes and the landlord says you flush too many wipes down the toilet. You argue and they make you pay for a plumber who's like "yea they all do that DONT USE WIPES!!!!!One!!!" And then finally after getting to know every other plumber in town, one offers to run a camera for free and shows you that the main line is fucking falling apart and that's why it keeps plugging up.

TBH sewer main inspections should be required any time someone wants to rent a house out.