What went down our toilet?

I own a  small apartment  building with various rented units.  I try to take great care of the property and keep up with any necessary maintenance and repairs.  It can be quite a challenge and harshly frustrating.  Very often, the renters are not considerate or careful, and because of this behavior that oftentimes cause damage to my property.  While I can manage the easy things, such as caring for the lawn, painting,  and replacing light bulbs, I hire professionals for the more difficult tasks.   I am constantly calling an electrician, and HVAC corporation and professional plumbers , which is rather expensive.  However, I feel it is necessary to hire a licensed workers to ensure safety and integrity of the the property.  I don’t get mad when the gas furnace or water gas furnace wears out after twenty years, or the pipes corrode.  I am willing to replace the electrical plan to accommodate the need for more outlets, exterior lighting or a security system.  What aggravates me is the repairs that are directly caused by the negligence or stupidity of the renters.  I once had a renter who assumed that there was a garbage disposable in the dining room.  She dumped a whole pot of mashed potatoes down the sink.  She jammed the drain so badly that I had to pay a licensed plumber to resolve the issue.  I’ve also had a renter flush a stick of deodorant down the toilet.  The stick got stuck midway down the  pipes and resulted in a huge problem.  We couldn’t reach the obstruction with a plumber’s snake, plus no amount of plunging would move it.  Once again, I hired a professional plumber to take the pipes apart to find and remove the obstruction.  This cost me a ton of money and was totally avoidable.  

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