It is difficult to give you an answer. Since every store in every state is different. Besides, there are several types of contact lenses. And the prices is different from each type of contact lenses. So, the cheapest one is over $10 / box. But the higher priced contact lenses is over $40. So, How much you will spend depending on which type of contact lenses you choose. If you want to know the price of specific contact lenses, you can go their sites at http://www.bestcontacts.com.
The price differs based on the different brands and quality. And I never buy the contact lenses at americas best. You'd better go to the online store and have a look. If you want to buy the ones with good quality, I think the price must be a little high. The common ones may be just about $20