\RequirePackage{scrletter}
\LoadLetterOption{DIN}
+\newkomavar{taxpoint}
\newkomavar{transaction}
\newkomavar[\lieferschein{}~\nr]{delivery}
\newkomavar[\angebot{}~\nr]{quote}
\locationentry{quote}
\locationentry{orderID}
\locationentry{projectID}
+ \locationentry{taxpoint}
\locationentry[\ansprechpartner]{fromname}
\locationentry{fromphone}
\locationentry*{fromemail}