"I appraised a single family residence for a good lender client about a year and a half ago. Today I got a call from another lender wanting an "update". I explained to this guy who called today that I could not do an "update"; but, rather that this would have to be a new assignment. I also explained that I was really busy right now and was unable to take the job. The guy started yelling at me that the loan was about to close and that if I did not get them an "update" ASAP he would sue. The truth is that this lender refused to pay a friend of mine a while back and had to be taken to small claims court before they paid up. I don't want to work for a company like that. Do I have anything to worry about"

Not at all.  You were correct in everything you said and you have no obligation to accept an assignment just because a lender threatens you.  I suspect this lender got a copy of your old appraisal and relied on it (without justification) to make a loan.  Now they need an appraisal report in their files and are trying to bully you into doing something you do not want to do.  This is their problem, not yours.

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