Altatac via Rakuten offers the refurbished D-Link Day & Night WiFi Security Camera in White for $19.99. With free shipping, that's tied with our December mention and the lowest price we could find for a refurb by $11. It features sound and motion detection, night vision up to 16 feet, and video resolutions up to 640x480 at 30 fps. It pairs with the mydlink app.

Note: A 90-day warranty applies, but it's unclear who backs it.