\documentclass[twoside]{scrartcl}
\usepackage[frame]{xy}
\usepackage{tabularx}
\usepackage[latin1]{inputenc}
\setlength{\voffset}{0.5cm}
\setlength{\hoffset}{-2.0cm}
\setlength{\topmargin}{0cm}
\setlength{\headheight}{0.5cm}
\setlength{\headsep}{1cm}
\setlength{\topskip}{0pt}
\setlength{\oddsidemargin}{1.0cm}
\setlength{\evensidemargin}{1.0cm}
\setlength{\textwidth}{18cm}
\setlength{\textheight}{24.5cm}
\setlength{\footskip}{1cm}
\setlength{\parindent}{0pt}
\renewcommand{\baselinestretch}{1}
\begin{document}

\newlength{\descrwidth}\setlength{\descrwidth}{10cm}

\newsavebox{\hdr}
\sbox{\hdr}{
  \fontfamily{cmss}\fontsize{10pt}{12pt}\selectfont

  \parbox{\textwidth}{
    \parbox[b]{12cm}{
      <%company%>
      
      <%address%>}\hfill
    \begin{tabular}[b]{rr@{}}
    Tel & <%tel%>\\
    Fax & <%fax%>
    \end{tabular}

    \rule[1.5ex]{\textwidth}{0.5pt}
  }
}
    
\fontfamily{cmss}\fontshape{n}\selectfont

\markboth{<%company%>\hfill <%invnumber%>}{\usebox{\hdr}}

\pagestyle{myheadings}
%\thispagestyle{empty}     use this with letterhead paper

<%pagebreak 65 27 48%>
\end{tabular*}

  \rule{\textwidth}{2pt}
  
  \hfill
  \begin{tabularx}{7cm}{Xr@{}}
  \textbf{Totale riga} & \textbf{<%sumcarriedforward%>} \\
  \end{tabularx}

\newpage

\markright{<%company%>\hfill <%invnumber%>}

\vspace*{-12pt}

\begin{tabular*}{\textwidth}{@{}lp{\descrwidth}@{\extracolsep\fill}rlrrr@{}}
  \textbf{Codice} & \textbf{Descrizione} & \textbf{Quantita'} &
    \textbf{Unita'} & \textbf{Prezzo} & \textbf{Sc.} & \textbf{Totale righe} \\
  & carried forward from page <%lastpage%> & & & & & <%sumcarriedforward%> \\
<%end pagebreak%>


\fontfamily{cmss}\fontsize{10pt}{12pt}\selectfont

\vspace*{0.5cm}

\parbox[t]{1cm}{\hfill}
  \parbox[t]{10.5cm}{
  \textbf{Sede legale:}
  \vspace{0.5cm}

<%name%>

<%address1%>

<%if address2%>
<%address2%>
<%end address2%>

<%city%> <%state%> <%zipcode%>

<%if country%>
<%country%>
<%end country%>

\vspace{0.3cm}

%<%if contact%>
%Attn: <%contact%>
%\vspace{0.3cm}
%<%end contact%>
\vspace{0.5cm}

<%if customerphone%>
Telefono: <%customerphone%>
<%end customerphone%>

<%if customerfax%>
Fax: <%customerfax%>
<%end customerfax%>

<%email%>
}
\parbox[t]{7.5cm}{
\textbf{Inviare fatttura a:}
\vspace{0.5cm}

<%shiptoname%>

<%shiptoaddress1%>

<%if shiptoaddress2%>
<%shiptoaddress2%>
<%end shiptoaddress2%>

<%shiptocity%> <%shiptostate%> <%shiptozipcode%>

<%if shiptocountry%>
<%shiptocountry%>
<%end shiptocountry%>

\vspace{0.3cm}

\vspace{0.3cm}

<%if shiptocontact%>
Attn: <%shiptocontact%>
\vspace{0.3cm}
<%end shiptocontact%>

<%if shiptophone%>
Tel: <%shiptophone%>
<%end shiptophone%>

<%if shiptofax%>
Fax: <%shiptofax%>
<%end shiptofax%>

<%shiptoemail%>
}
\hfill

\vspace{1cm}

\textbf{FATTURA}
\hfill

\vspace{1cm}

\begin{tabular}[t]{l@{\hspace{0.3cm}}l}
  \textbf{Data fattura} & <%invdate%> \\
  \textbf{Numero fattura} & <%invnumber%> \\
  \textbf{Ordine} & <%ordnumber%>
\end{tabular}

\vspace{1cm}

\begin{tabular*}{\textwidth}{@{}lp{\descrwidth}@{\extracolsep\fill}rlrrr@{}}
  \textbf{Codice} & \textbf{Descrizione} & \textbf{Qt\`a} &
    \textbf{Un.} & \textbf{Prezzo} & \textbf{Sc.} & \textbf{Tot. riga} \\
<%foreach number%>
  <%number%> & <%description%> & <%qty%> &
    <%unit%> & <%sellprice%> & <%discount%> & <%linetotal%> \\
<%end number%>
\end{tabular*}


\parbox{\textwidth}{
\rule{\textwidth}{2pt}

\vspace{0.2cm}

\hfill
\begin{tabularx}{7cm}{Xr@{}}
  \textbf{Totale righe} & \textbf{<%subtotal%>} \\
<%foreach tax%>
  <%taxdescription%>: <%taxrate%>\% & <%tax%>\\
<%end tax%>
<%if paid%>
  \textbf{Pagato} & - <%paid%> \\
<%end paid%>
  \hline
  \textbf{Totale da pagare} & \textbf{<%total%>} \\
\end{tabularx}

\vspace{0.3cm}

\hfill
  Tutti i prezzi sono espressi in valuta \textbf{<%currency%>}.

\vspace{12pt}

<%if notes%>
  <%notes%>
<%end if%>

}

\vfill

<%if paid%>
\begin{tabularx}{10cm}{@{}lXlr@{}}
  \textbf{Pagamenti} & & & \\
  \hline
  \textbf{Data} & \textbf{Conto} & \textbf{Documento di riferimento} & \textbf{Importo} \\
<%end paid%>
<%foreach payment%>
  <%paymentdate%> & <%paymentaccount%> & <%paymentsource%> & <%payment%> \\
<%end payment%>
<%if paid%>
\end{tabularx}
<%end paid%>

\vspace{1cm}

%\centerline{\textbf{Grazie per averci scelto!}}

\renewcommand{\thefootnote}{\fnsymbol{footnote}}

\footnotetext[1]{\tiny
Per i pagamenti successivi alla scadenza della fattura sara'
addebitato l'interesse legale, aumentato di due punti percentuali, fino al
pagamento completo.
}

\end{document}