My tenants HATE each other, expect me to fix their issues

[Nathan Yaun]

I have an upper lower duplex with very nice hardwood floors.  The upper renters are a husband a wife with two dogs and have been there for 10 years.  I have owned the place for 1 year.  The lower tenant is just a mid 40s loaner that minds his own but is grumpy.  Until a month or two ago they all worked for the same towing company.  At some point the guy down stairs was told that the uppers "have it out for him" .  Ever sincesince he is calling me about issues that I can't prove happened.  His water heater didn't work but now it does.  His garage remote didnt work but now it does.  Now the dogs are to loud upstairs and lord knows that he's doing it all on purpose to drive him out.  I'm not going to accuse the guy in the upper of anything for no reason.  He has been very helpful and even just coverscoversof the minor repairs himself.

I feel like this isn't my business.  I probably won't get away with calling the grumpy guy paranoid and, after all, he might not be.  They both legally have possession of the property that they are leasing and this isn't any different than not liking any neighbor that you have.  The other neighbor, in the house next door, calls me to complain about them parking the tow trucks in the driveway because he's a gumpy old pot head.  I could care less because its not harming the driveway.  I don't see why just because I own the property I have the be the group counselor.  I would like them to get along but don't care if they don't as long as they dont ruin the place.

I think you get it.  My questions is, how involved do I get in all of this drama?  How involved am I obligated to get?  Having my businesses best interest in mind of course.