The closer it is to April 15, the more reluctant you should be to take a new client.  If you have to ask, "Why are you just now getting around to thinking about taxes?", it's probably too late.  Exceptions for those whose former preparer was shot by an angry walk-in.  Or keeled over from a heart attack, because the stress just got to be too much.  (Verify that the guy asking, was not the final straw.)