We need to import from our current shopping cart (Pinnacle Cart) the data in customers, orders, and products into our Magento site. Orders and Customers must retain relationships, Orders retaining their correct order #. We have less than 70 products to import, Approximately 1000 users and 3000 orders.
First step would be for you to import existing data to testing server. Then we would test data and site.
Second step would be that once testing is over and the site is ready to go live the data from our old site that has accumulated since the first import would need to be imported and tested.