I file "Pay or Quit" notice followed by an unlawful detainer petition in state court.

That is why they have been unresponsive.In order to get the ball rolling here, assuming there is a Will leaving everything to the son who is trying to sell the property, the son must hire an Attorney to file the estate for probate, and obtain Letters Testamentary naming the son (if he is so named in the Will) as the representative of the estate.  

File a complaint and ask for damages.

Have them fill out a W-9 form, always pay with a check, and if total payments paid to them during the year are $600* or more, then filing a 1099 is appropriate.Also, you should get them to add you as an additional insured (or at least a certificate holder) and have their agent send a copy of their insurance to you directly.  

http://www.dre.ca.gov/files/pdf/guide_unlic_asst.p...2.

Big tip:  Filing an Memorandum of Interest at the county is almost worthless.  

Was wondering if there are any document in the "files" section on bigger pockets that others have found helpful in organizing & guiding you through the whole inspection period?

        @Mike MoRo          Are you in the process of getting title (filed suit) to the property and discovered there is this lien or have you recorded your deed and somehow discovered this?

I am filing an intervention form today.  

I also found out that there is a lawsuit filed against delinquent taxes.