PayPal secure IPN, recurring billing, customer bal payment

Expert PayPal developer with lots of verifyable PayPal experience. Secure IPN, Recurring monthly invoices, PayPal payment option in Customer Administration Page. Min 5 years development experience. Must be reputable and have excellent references. No criminal record. References required. Work should be completed in 2 to 3 days. Need to process product purchase orders via PayPal with IPN. Successful or declined email notifications will need to be generated. There needs to be an ability to continue to prompt the user to try another credit card until the user selects "No". After a successful payment our order tables will need to be updated. Confirm that the "payment_status" is "Completed," since IPNs are also sent for other results such as "Pending" or "Failed" Check that the "txn_id" is not a duplicate to prevent a fraudster from using reusing an old, completed transaction Validate that the "receiver_email" is an email address registered in your PayPal account, to prevent the payment from being sent to a fraudster's account Check other transaction details such as the item number and price to confirm that the price has not been changed Once you have completed the above checks, you may update your database with the IPN data and process the purchase. If you receive an "INVALID" notification, it should be treated as suspicious and be investigated. Need to setup recurring billing on PayPal for Monthly invoices. Firsr month's invoice will need to be prorated. Also need to determine the conditions that need to be in place before first month's invoice can be sent such as product needs to be shipped. We also have a condition that our customer is required to call us to activate the unit once he has received the unit. Customer may dalay the call but invoicing will commence even if the customer does not call 14 days after the ship date. If the customer calls before the 14 days then that day will be used as the first day of use and will be used to determine the prorated billing for the first month. Every susequent month the invoicing will be done via HTML formatted email invoices on the billing date. Post a successful invoice out invoice tables will need to be updated. Need to add to Customer Administration page ability to view all declined invoices with invoice details and total owing. Ability to pay the total owing via PayPal on the customer administration page. Post payment our invoice tables will need to be updated. Need to strat IMMEDIATELY. And be able to work wihout any interuptions until project is completed. Expect to work weekends if required. Expected to provide daily status report. Expected to provide the work broken down to daily tasks with what will be completed each day and when will the project be FULLY completed.