Amazon offers the refurbished Netgear Arlo Add-On HD Security Camera for $84.99 with free shipping. That's tied with our November mention and $35 under the best price we could find for a new one. It features magnetic mounting, night vision, live viewing, and wireless connection.

Note: It requires either the Arlo or Nighthawk R7000 camera kit. A 90-day Netgear warranty applies.