TJ,
I recently bought this "low tech" solution from amazon because my Dad has dementia and misplaces his keys and wallet all the time. It worked fine the only time we used it last week.

http://www.amazon.com/gp/product/B00AE4U6T2/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

1 ac pond LMB, BG, RES, CC