When trying to find combinations, we multiply the numbers of things we can add to it. There are 6 different types of bread, 4 different types of meat, and 7 different types of condiments plus the no condiment. Since for the meat and condiment, there's another possible outcome than having just 1 type of meat and no condiment, we multiply by two twice.

This means we have 6*4*2*7*2=**672 **different sandwiches.