Automated script for digital delivery via PayPal

I require an automated code/ script for digital delivery of items sold on eBay via PayPal The script should extract key information from the PayPal email which is sent to the seller when a payment is msde. The script should then check against a database for a matching item number or value, then automatically send an email to the buyer with a link to download their item. Please note, I have some knowledge of HTML, use of cPanel etc so please consider this when designing the script. I am confident to go in to my SQL and change some of the line items for example, so the script needs to be simple but I can make some edits occasionally (eg transferring host and changing database connection for example!) Key features: + Ability to extract email address, item number and value of purchase. + if there are multiple email addresses in the PayPal email, script should send to both addresses (ideally! Please let me know if this is a difficult job) + Script MUST NOT reply or send emails back to PayPal addresses. We can create a blacklist of addresses (eg anything ending in [login to view URL], .[login to view URL], [login to view URL] [login to view URL], updated via database) + It needs to be able to interpret all types of PayPal payment email. +some PayPal payment emails do not contain the item number. In this case it should check for the transaction amount instead and match from the database.. (In our selection of products, there is only ever one item at the price. No two items have the same price. + Does not have to run instantly (eg could be a chron job every 15min to check and send responses, if that is more cost effective. But if it can run instantly then even better) + It should work simultaneously with multiple email accounts - max 3 at any one time. Simple web form needed to add and update login details (I can paste in the server details, port, username, password, ssl/tls settings if you the developer think that is the best approach). Note: it might be easier just to install three times on the same server but different databases and file/folder location. Let me know what you think? + Gmail is the main email provider that we use for this. + the script should CC one email address to the response email... This is the same for all accounts. + The script must be able to handle multiple different items to deliver. + the response email (sent to the customer) can be simple plain text, no formatting necessary. I will want to send a few lines in the automated response. This should be the same for all items and all email accounts. Simple email subject eg "download your purchase". If I need to update these then I'm happy to edit the php/html/database directly. No need for admin page for this. + It must be straightforward to add and remove item numbers, download links, and email accounts. This does not have to be 'fancy', a simple web page would be fine and then I can manually add password protection to the pages via cPanel. I imagine a simple form on a page with various headings like Name, Item number, Price, Download link.... No need for modify option, I'll just delete and add again if necessary. + Ideally any admin pages will work on smartphone/ tablet so I can update on the move. + it should store the email responses in a database/ similar for record keeping. Then I can go to My SQL and take a look in raw format (no fancy formatting needed, only simple). Should be unlimited but I can clear out/delete every few months. Should record date, time, email address sent to, item number and link. Key notes: + Script not required to log in to eBay or PayPal. + file upload etc not needed, I will just paste in direct links go download item stored on Dropbox etc. + Only needs to work for individual purchases (eg one eBook). We will manually manage when the transaction includes multiple items. + If there is no match for the item (based on eBay item number and/or value) in the database, then it can ignore this email. + it does not need to match by title/ name of the item. + If there are multiple item numbers in the PayPal email, then it can ignore the email. + Unread emails only + Think LONG TERM: the script needs to be able to handle changes in layout of emails from PayPal etc. Eg changes in currency symbol. + the script should ignore any other emails + Must retain all emails on the server (eg use IMAP to check the server for new emails). Systems requirements + Works with cPanel + Must be straightforward to transfer to a new hosting provider if necessary. Admin page should be accessible by mobile device. Please note, I have some knowledge of HTML, use of cPanel etc so please consider this when designing the script. I am confident to go in to my SQL and change some of the line items for example, so the script needs to be simple but I can make some edits occasionally (eg transferring host and changing database connection for example!) Training and support + Developer should provide me with a walkthrough of how to use all the functions + developer should be contactable by email, Skype or similar messaging. + developer should offer a 3 month warranty at minimum, agreeing to fix any errors during this period. + cost should include set up on one of my cPanel hosting accounts.