How do you secure a loan against an estate?

[Brett K.]

I'm trying to sell a property to a buyer who wants to pay cash but the $$ is tied up in an estate.  The attorney will not allow her to put a mortgage on a free and clear house and he won't disperse any money until February.  

I see ads to borrow money against lawsuit winnings, tax returns, and estates.  How do they do it?  I've called a  couple of attorneys and no body seems to know how.