Dear Sir or Madam: We regret that we cannot vouch for the reliability of ____ (company). Our experience dealing with this firm has been unsatisfactory. During the past ___ (time period) that we have been having a business relationship with ______ (company), they have repeatedly failed to meet their financial obligations. In fact, right now they owe us ________ (amount) for purchases made over a period of _________ (time). We know that this information will remain in confidence and we hope that it will be helpful to you. Sincerely yours, (name) (title)