Order price customization

[lobebe]

Please can anyone tell me what is error in the code below:

$html .= $this->getHtmlRow ('STANDARD_AMOUNT', ('$osp = $currency->priceDisplay ($order['details']['BT']->order_salesPrice);
               $os= $currency->priceDisplay ($order['details']['BT']->order_shipment);
               $opt = $currency->priceDisplay ($order['details']['BT']->order_payment_tax);
               $op= $currency->priceDisplay ($order['details']['BT']->order_payment);
               $cd = $currency->priceDisplay ($order['details']['BT']->coupon_discount);
               $ot = ($osp + $os + $opt +$op + $cd);
               echo number_format($ot,2,',','').'€''), "vmorder-done-amount");

Thank you