List of forms and connection of payment LiqPay

It is necessary to make a simple calculator (the prices of the selected positions are summarized when marked with a gallon). The amount of selected positions by clicking the Payment button is transferred to a cashback for online payment. After payment information about successful payment and the data from the form are sent to the email + the possibility to attach the file to the form of sending. There is a form of appearance. You need to turn and make it functional.