Woot has the Used Blink XT2 Outdoor/Indoor Smart Security 2-Camera Kit in very good condition for $39.99 and 3 Blink Camera Kit for $49.99 for a limited time. Shipping adds $5 but is Free for Amazon Prime Members.
The Blink XT2 is my Security Camera of choice. They are packed with features, affordable, and extremely easy to setup. They can be used indoor or outdoor and have an estimated 2-year battery life. It runs over your wireless connection and features 1080P resolution with a 110-degree field of view, motion-activated instant-on recording, customizable motion detection, 2-way audio, live-view recording, and integration of Amazon Alexa.
These units have been tested and verified internally by Amazon to meet the specified product condition, but may have cosmetic blemishes. The units may be repackaged and sold in a brown box.