So if the tenant caused the problem (i.e. too much toilet paper, flushing feminine products, etc) then they should pay for it. 

Here's basically what we have on hand.Plumbing stuffCouple p trapstoilet flush valvesbathroom faucetkitchen faucetflex water supply linesshut off valves, compression since piping in building is copperone extra dishwasher, a used one left over from a renovation, but it worksone extra garbage disposalcouple tubes of 100% silicone caulkOther stuffmiscellaneous electrical like outlet covers and switchessmoke detectorspaintdrywall mud for small repairshalf a sheet of 1/2" drywall for repairscouple dome ceiling lightsspare cabinet doors and hardwareinterior door handle setspretty much a full set of tools so I don't have to remember to bring anything with me when I go over there.I guess that's about it. 

After we brought a plumber out to take a look, they confirmed that the main pipe connecting the house to the street needs to be replaced with PVC because it's no longer safe to flush solids through it. 

Higher maintenance costs because tenants don’t understand what not to flush or when to contact us is a reality.

Flushing as well?

Those types of issues will be flushed out in the case but that does not preclude liabilty protection of the LLC.  

The seller can just say that the tenants are flushing stuff down the toilets that is causing the back up.Ask your attorneyGino

I mean certainly a 40 year title search will flush out the issues but I would be wondering the same thing.

Place was turned into office condos during the bubble, and when it burst the place turned into a mess as each floor has went through the foreclosure process and most out of state non performing investors have been weeded/flushed out.  

Look for 1.28 gallons per flush.