[rushpat]

You might want to consider sending a Notice of Default with Opportunity to Cure, an additional 3 or 10 days (I'm not sure of the standard... I used 10 days). This gives the appearance that you've truly tried to give them every chance and more to fulfill their obligations.

Afterwards, when you don't hear anything again after the final time limit, then issue a Notice of Default, or non-response, whatever you prefer, have it notarized, publish in the county recorder (some are getting them filed in the federal district courts under the Misc file). Some may also want to publish it in the legal section of the newspaper as a public notice. Then send a final copy of that to the IRS. You might also send a warning of estoppel with this.

I'm trying to find out more about the steps afterwards.