Ends 1/14. Amazon has the KTeco 720p Security Camera System w/ 4 Cameras for $110 - $41 off with coupon 7PVNADYX = $69 with free shipping. Features four 720p cameras, motion detection, and night vision up to 66 feet.
eBay has the Remo+ DoorCam WiFi Smart Over-the-Door Camera, (DCMU-1706) for $99 with free shipping. List price: $199. It fits over your door and features a 160° field of vision.
Amazon has the Wyze Cam 1080p Wi-Fi Indoor Smart Camera (WYZECP1) for $38 with free shipping. Features 2.4GHz-band connectivity, Amazon Alexa compatibility, 6 IR LEDs for night vision up to 30 feet, motion and sound detection with 2-way audio and motion tracking, 110°/sec rotation speed, 360° horizontal range, 93° vertical range.
Has good Amazon Reviews.
Amazon has the Actitop 4K 48-Megapixel WiFi Ultra HD Digital Camcorder for $243 - $73 off with coupon 48FYV2JF = $170 with free shipping. Features 4K (2160p) video recording at 24 fps (1080p at 60 fps), 3" IPS touchscreen display, wide-angle and macro lenses, external microphone, LED light and night vision.