RAM + ROM: 4GB RAM 64GB ROM, Feature: GPS, Camera: 12.0MP + 2.0MP back camera + 8.0MP front camera, Fingerprint Sensor, Beidou, CPU: Helio P35 Octa-core 2.3GHz, SIM Card: Nano SIM card + Nano SIM card / micro SD card, Gravity Sensor, A-GPS, Geomagnetic Sensor, Glonass, Bluetooth: 4.2, Display: 5.84 inch 2280x 1080 Resolution Capacitive Screen, Gyroscope, Ambient Light Sensor, OS: Android 8.1, Accelerator, Sensor: E-compass, Distance Sensor.
Basically copy coupon, view price history or create e-mail price alert. What is best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in Hong Kong. Well, there is one coupon available right now.
Link: Banggood product page
1. ($121.99): Email5
coupon code has to be applied in shop’s cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): 4BGMP3, 4BGMP3C, plfonall, 4BGMP3CL, 5BGXMP, BGMP2, BG5MP, BG6MP, affiliate6, BGILMipaly, BGEUMiPlay, aff7off, BGMIPLAY, BGMIPLAY2, BGEMP, bgssaff9, BGEMPCCL, BG7PLAY, BG7PLAYEU, BGPAYPALSS, BG8MP, BG8MP2, BG8MP6, BG8MPCL, BGMPLAY, od7off, BGPUREMIPLAY, BGaDmITAd, BG36MP, BG36MPEU, BG10MP, BG36MPCL, BGAFF10OFF, 7d18f7
(probably won’t work, but you can try them out)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – Xiaomi Mi Play 4/64GB Global Blue [EU] ($-3)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi Mi Play 4/64GB Global Black. The lowest price was: $99.99.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).