Cheapest I've seen this from a UK seller. Got lots of static/movable YI cameras and they have been very good.
The free PC app lets you set up CCTV-style multiview in 2x2 or 3x3 layout, as well as view/control the cameras. The phone app is also pretty good and reliable.
You can add a microSD card to record motion-detected events and get a push notification to your phone. You can view a 6 second clip without a card or the whole event with a card. No subscription charges necessary unless you want to store the clips on YI's cloud storage.
The only problems I have had have been when the SD card fails when they go into a reboot cycle, but pop the card out or replace it and they're back to normal.
In my experience they do kind-of work with Google Home Hub displays, but not very reliably - you'll get a quick burst of live video then a "can't connect" message followed by another quick burst and so on.
Here's the blurb:
- 360° COVERAGE IN FULL HD WITH ADVANCED NIGHT VISION - Live stream videos and footage in 1080P at 20fps - Pan-tilt rotation with remote control - 110° wide-angle with 4x digital zoom - Advanced night vision with adjustable IR lights and status LED (ideal for undisrupted sleep) via app YI Home.
- MOTION DETECTION & TRACKING WITH PUSH NOTIFICATIONS - Motion detection with 6 second video-clip of the detected activity - Motion tracking with 10 seconds video-clip of the tracked activity - Push notifications on smartphone with adjustable frequency and sensitivity level via YI Home app.
- PANORAMIC & BOOKMARKS MODES - PANORAMIC CRUISE MODE: The security camera will automatically monitor the area 360° by rotating 20° every 10 seconds. BOOKMARKS MODE: The user can bookmark up to 8 favorite zones to cruise through. Ideal for large spaces.
- TWO-WAY AUDIO: talk and listen via the Integrated mic & speaker - MULTIPLE INSTALLATION OPTIONS: standard vertical placement and wall / ceiling mounting thanks to the included base tray and screws - WORKS WITH ALEXA (ECHO SHOW): See your wi-fi camera’s live stream directly on your Echo Show’s screen.
- SECURE STORAGE ON YI CLOUD: Keep your footage safe from damage, theft or loss with YI Cloud! YI Cloud ensures loop recording on YI Cloud of all the videos of the detected activity, with monthly and annual subscription plans available for extended storage and recording options - LOCAL STORAGE: Supported Micro SD cards up to 64 GB, class 4 and above.