Db and logic updates and payment gateway incorporation

This is a project that needs to mainly put right the db updates for the services checkout process and to incorporate a payment gateway after that checkout. The tasks broadly are (details of minute tasks will all be stated again when full specs are provided): 1. Get the services info such as the service name, the price etc from a mysql based table thats already existing, and display in in our site to sell 2. After the Service selection by a customer and checkout, provide the payment options such as Mastercard, visa, paypal etc by a Payment gateway 3. After success payment, generate the invoice and undertake customization of the existing php code for the purpose of the Registration. 4. Update all database records that are part of this entire workflow such as the before tax total, the tax amount , the final amount. 5. Handle recurring payment automatically as indicated by the customer. Hence during the payment, the must allow the customer to indicate that they would want the same service to be automatically renewed upon close to expiry date of the service and be charged and invoiced automatically also to them 6. Handle refund of the payment amounts both partial and full refunds. Because the existing site permits cash refunds as well hence this must also be taken into account when refunding. The design of the refund will be provided. Freelancer can suggest the payment gateway that they have used before (prefereably the same region as that of me the Client) . Thank you.