I'm in the design phase and would like some ideas on the best options to review. We want to be able to getprice/update price from an external datasource throughout the user experience (catalog, cart, checkout). CVS uploads won't work because it's not real-time. We may pass paramaters that adjust the price or other values like shipping charges, expedite fees, etc. The logic is already built in our external app. We'd like good performance for 100's and 1000s of SKUs.