Shopping Cart Software

Is it possible to have it calculate rates from multiple warehouses?

To set up shipping for your main warehouse you will need to go to step #6 "Shipping Options" in the Cart Settings section of the cart, and fill in the Drop Ship Zip settings.

If you have products that come from a specific warehouse that is different from your main warehouse, then you will go into the add to cart button itself to specify a warehouse location.

For more information regarding the button Field 12: itemdropshipzip (optional) the other fields and their placement, go here.