# sellprice_total_including_tax = qty * fxsellprice * (1-discount) / price_factor * exchangerate
# $ar->{sellprice_total_including_tax} = $form->round_amount( $ar->{qty} * ( $ar->{fxsellprice} * ( 1 - $ar->{discount} ) ) / $ar->{price_factor}, $form->{"decimalplaces"});
# sellprice_total_including_tax = qty * fxsellprice * (1-discount) / price_factor * exchangerate
# $ar->{sellprice_total_including_tax} = $form->round_amount( $ar->{qty} * ( $ar->{fxsellprice} * ( 1 - $ar->{discount} ) ) / $ar->{price_factor}, $form->{"decimalplaces"});