Your lawyer will also be able to advise when it's time to get the authorities involved.

Ask the condemning authority. 

Sec8 in it's actual practical implementation varies a GREAT deal by the specific housing authority.

@Tal Perry The best way is to get authorized with the mortgage servicer and ask them.

I am an Illinois real estate attorney and I don't have a quick fix/alternative solution.Hindsight is 20/20 but in future, you would do a walk thru after the heavy furniture is moved out of the house.When you say "moving company", does it look like the company might be incorporated in  the state where the house is located or elsewhere.I say this because you may be dealing with an employee at the company who doesn't care or doesn't want his superiors to know what is happening.In Illinois, I can search on the Secretary of State's office to see if the company is incorporated and find the name and address of their authorized Agent and the Company's corporate officers.You really need to contact the President or Attorney/Law Firm and tell them the situation, including the fact that their customers agree that the damage was caused by their company. 

Tell them to call you back once they get their paperwork.2) Fill out the form to get the property added to the local Housing Authority available property list.

@Charlie MooreCall your local Fair Housing Authority.

The New York City Housing Authority (NYCHA) is the largest public housing authority in North America. 

I already have a “Statement of Authority.”

If you don't and they discover it during a claim, then you'll possibly lose all coverage.You should also confirm with zoning that your duplex is authorized.