301448 Membership Ecommerce Site

I need an ecommerce script developed. Currently I have Amember to handle the access to the secured site, It basically does everything I want, except Amember doesn't support multiple quanities or "Seats" at sign up. Below is the break down on the major features. Please email me if you need any additional information. The script needs to do the following.... Take all user data and put it in MYSQL database. Must be able to check for expired subscription and prevent them from getting in the system Must be able to authorize a credit card (Visa/MC) with [login to view URL] Must be able to handle quantity according to these price rules: First 'Seat' = $25 a month Each additional = $10 a month Must be able to do reoccurring billing (each month on expire renew by card on record) Users must be able to cancel subscription at any time (no refund for unused portion) Must be able to send reminder emails, confirmation emails, and "sorry to see you go" emails Email to confirm subscription on sign up (template) Email 1 week before expire to remind user. Email 1 day before auto renewal Email 1 week after expire or when user cancels Must be able to handle coupons for discounts (or tracking my advertising campaigns Coupons can created from an admin panel May give 10% off, or additional time Admin panel to configure prices, length of time, email templates, coupons, and track users, amount made, etc. The Virtual Help desk is currently sold 4 ways: Month to Month - $25 for first PC, $10 for each after 6 Months - same prices, but with 6 months commitment user will get an extra month FREE (7 Months) 1 Year - same prices, but with 1 year commitment user will get an extra 3 months FREE (15 Months) One Time - Price for One time use is $15 - their account is not auto renewed, and username and password expires next day.