Question about foreclosure clean up business?

I do a lot of work and the Handi work for my GF's father's who has some commercial properties. I've heard of people doing business "to clean up the mess left after a foreclosure. I wonder which is usually the customer? Is the bank to pay someone to clean up the property or is real estate agent who hires a person to clean up the property they sell? What is typical wage "as: Is it per job or not billed by the hour and give an estimate of how many hours do you think they take, I'm sure that varies from state to state, but is there any license or is just a basic business license and insurance? Is it beneficial to diversify and paint the walls and make things or is it better just to keep clean?

The banks are the customers. People have these contracts Ted pocket. They do not get paid much. I think it's something like 80 pounds for the property, but for this they have to provide new locks on the door.