Summarizing all line items in tax invoice

Hi,

Can we summarize all the line items from the sales order into a single line item for invoice output ,,

ex. In some countries tax authorities will give sequential tax numbering for invoice, ( you can not use the same sequential number for page 2) , whatever the total invoice value should be in 1 page..

sales order

m1- 10pc- 100 usd

m2- 5 pc- 25 usd

total order value 125 usd

invoice--

total order value 125 usd

tax xxx

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xxxxxx

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And the out put should triggered as 2 copies...one for sustomer one for client

Thanks in advance for your valuable inputs