Thank you for attention to ours posts.
First, I don't think the cost of the fingerprint reader needs 50k, fingerprint payment has been used in a lot of scenes, such as Apple pay, iPhone's touch ID, Samsung also collaborated with Alipay.http://www.gottabemobile.com/2014/07/14/how-to-use-the-galaxy-s5-fingerprint-scanner/
Secondly, No absolute safety. So we use RFID medium, and RFID communicate need to use keyA/keyB. keyA/keyB is generated based on personal password. If you do not know the personal password, you cann't forge a new RFID medium to communicate.
Finally, everything needs to touch the hardware wallet.

Security is a set of systems, not just a step.
http://i.imgur.com/Xtp2rcr.jpg