We run a Magento store in which gold and silver is sold. We need our product prices to be calculated dynamically on the fly so they are always correct.
-Calculations must be: Product Price = precious metals price + base + commission
-We need a to acquire a precious metals api feed, preferably free.
-There needs to be some kind of time limit on each page, so you can't leave it open for a while the prices are changing (or have the prices automatically change on the screen & cart)
-There needs to be some kind of fail-safe if the api fails that the pricing is correct.
-Anything else you can think of that we'll need to make this work...