Costco.com and Costco BM are selling the Ring Alarm Wireless 10-piece Security Kit and Ring Video Doorbell 2 with 12 Months Ring Protect Plus for $100 off if bought together. The benefit here is that the 12 months Ring Plus give you full live monitoring for your alarm system for 1 year also.
I set it up yesterday. Make sure you set up the Doorbell first since the free 1 year comes with it. Then you just add the base station of the security kit to the account and you can proceed to setup your monitoring service.
Amazon sells the Doorbell 2 without the 12 months Protect Plus ($100), so that's basically you are buying the security kit and getting the doorbell for free.
Ring Alarm Wireless 10-piece Security Kit [costco.com]
Ring Video Doorbell 2 with 12 Months Ring Protect Plus [costco.com]