Add voucher feature + paypal checkout on existing shop/form built in PHP

Add voucher feature + paypal checkout on existing shop/form built in PHP. Add city to table "users". The website consist of a one landing page. And confirmation page. Emails are sent after order are placed. At checkout, user: - select a city* - select a number of seat - enter his contact details* - enter the contact details for each additional seats* - choose products/qty (tshirt, bag...) - upload a receipt for bank direct bank deposit and submit the order - or choose upload later and submit the order - the system sends a confirmation email in both cases - the system generates a QR code later (after manual check of payment/receipt) Voucher table is structured as follow: -- Table structure for table `coupons_vouchers` CREATE TABLE `coupons_vouchers` ( `id` int(11) NOT NULL, `code_type` text NOT NULL, `discount_val` text NOT NULL, `discount_unit` text NOT NULL, `code` text NOT NULL, `attributed_to` text NOT NULL, `start_date` datetime NOT NULL, `end_date` datetime NOT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1; See screenshot for database and tables structure. Table orders contains the details of the main person (= emergency_contact) Table users contains the details of the emergency_contact + details for additional seats contacts.