It would help to have contacts with a bank or other home lender.
You might try contacting a few and asking if they need contractors who can clean out homes. I know a lady who started out doing lawn care for bank owned properties, and now she employs over 100 people, and all they do is turn around foreclosure properties.
There are likely some things they will want from you. Are you licensed? Do you have insurance to protect them and your workers? Do you have access to trucks, dumpsters and other equipment you may need?