Not only do they not repay funds, they claim we owe them additional funding for renovations that never actually happen. 

I suggested using traps, and there were no further complaints until November 17.I promptly hired a professional for rodent treatment, which was completed within 10 days.The tenant is now demanding 3 months of free rent, claiming the property was "infected," despite my timely response and corrective measures.I need assistance crafting a response to this demand within 2 days to avoid escalation to small claims court.

Also prevented us from making wrong statements on our part which would have reduced the claim.3.  

I manage 400 rentals and the most significant claim ever filed was a kitchen fire that cost $20,000.

That said, we have not made a claim up until the fire. 2.

Now she claims it’s a service dog because his husband is vet and she should be legally allowed to keep the dog and does not need pet fee or pet deposit or monthly pet rent. 

I don't know what area you are in, but generally just take them to Small Claims Court.

But then we have to get into talking about the passive loss rules, which may prevent you from actually being able to claim a tax loss if the deduction is more than your rental or other passive income.Or you can claim the actual expenses (gas, insurance, etc) for the vehicle and regular depreciation, proportioned by the percent of business use of the vehicle.  

If yes, am I eligible for a 1031 exchange even though I claimed the home as my primary residence when it was rented? 

The previous owner claims they never had the titles to these trailers, so that is not option.