BuyDig via eBay offers the Yale Locks Bluetooth Key Free Assure Lock in Satin Nickel for $137.99 with free shipping. That's the lowest price we could find by $81. It enables you to lock and unlock your home via your smartphone, and is compatible with Amazon Alexa (lock & check lock status only) and most Z-Wave home automation and alarm systems, including SmartThings. It also allows you to share digital keys, view access history, receive notifications, create pin codes, and customize settings.