Strengthening 2-Step Verification with Security Key

I was reading the Google article, Strengthening 2-Step Verification with Security Key, and decided to see how much strengthening my security would cost. Everyone says they want better security until they see the price tag. Surprisingly a security key does not cost much. The cheapest key on Amazon comes from Plug-up International, costs $5.99 with $2.00 postage, and my estimated delivery date is November 10. I can do that!