This question also has an answer here (in German):
Schlussformel für Beschwerdebrief?
I am writing a complaint letter and want to know how to end it. The issue was pretty bad and I'm very unsatisfied/offended with the service, so does "Mit freundlichen Grüßen" sound ironic? (I'm definitely not freundlich in the letter).
Is there something more neutral like the English Regards or Sincerely?