Amazon has the eufy Security eufyCam S330 4K Wireless 4-Camera Kit w/ Integrated Solar Panels (eufyCam 3) on sale for $380 with free shipping. eufy Security eufyCam S330 Add-on Camera is $123.

• Requires just two hours of sunlight for continuous operation. 
• Local recording, no monthly subscription (upgradable storage to up to 16TB)
• Works with Alexa and the Google Assistant. Two-way audio, Face Recognition AI