Create an email alert system for prices

Create an email alert system for set price limits, high and low. Currently prices are displayed in my website using API. I need users to be able to subscribe to price alerts. You may or may not need to store the prices in a database for this. I am unsure how it can work. Also add price alert subscribers automatically to the subscribe2 plugin database which is already functional for blog posts. There should be ability to control the frequency of emails etc. I need a fully functional backend console with login to see and manage the price alert subscriptions, view, delete, see sent email box, email templates and customize it and whatever you can think to make a well managed alert system. Alerts should be activated after email confirmations only. Thanks