The A/C unit in my rental froze up one day during peak summer (in July). I was out of town and I authorized my tenants to contact an AC repair company as my regular AC guy had retired.The AC repair company sent a tech...

There is no agreement and we don't want to continue with someone that is threatening a lawsuit and trying to force a sale based on threats. 

You aren't lowering a  potential criminal threat to the neighbors.

Unfortunately anything above a 15 year fixed seems a bit risky, especially with the threat of a possible economic crisis upon us.

No late or missed payments by the owners since the mortgage. may 5th, 2011, under threat of foreclosure son issues himself as mortgagee a forced 10 month simultaneous addon of $3,102.60 to the mortgage as a result of him redeeming property tax certificate.

They sound like they are trying to get money out of you with the threats.

There is an implied threat that, if you don't use their repair service, you will have to pay again for an inspection after the repairs.

Normally the threat of destroying their credit is enough to change their mind assuming you are not dealing with C/D class tenants.

Although it was only a stones throw from the ocean,  it was the marsh-land to the south that was a threat and seemed to come alive in past winter months.Now this property was NOT in the flood zone, not yet. 

- As far as requiring renters insurance, it mitigates the threat of a lawsuit.