Hello,
For the Invoice PDF changing these lines through the "plugins/hikashop/attachinvoice/attachinvoice/invoice.php" file :
<td colspan="3" class="newarea">
<?php echo JText::_( 'HIKASHOP_TOTAL' ); ?>
</td>
<td class="price" >
<?php echo $currencyHelper->format($order->order_full_price,$order->order_currency_id); ?>
</td>
by :
<td colspan="3" class="newarea">
<?php echo JText::_( 'HIKASHOP_TOTAL' ); ?>
</td>
<td class="price" >
<?php echo $currencyHelper->format($order->order_full_price,$order->order_currency_id);?> (<?php echo $currencyHelper->format($currencyHelper->convertUniquePrice($order->order_full_price,$order->order_currency_id,hikashop_getCurrency()),hikashop_getCurrency());?>)
</td>
Will probably do the job.