You can create price alert here, copy coupons and view price history. Do you want to know what the best price is?
Sensing Range 0-3m / < 120°, Size 149x 61x 56mm / 5.87"x 2.4"x 2.2", Auto Light Times 1500-1800 times, Lamp Color Temperature 3000k, Battery Capacity 500mAh, Power 0.25W, Turn On Time 20h, Auto Light Time 20s, Weight 100g, Charging Lampe Red / Blue, Brightness Impression < 3lm, Standby Time 10 times ·180 Day, Input Voltage USB 5V, 3 Mode Auto / Off / On, Charger Port Micro USB, Light Brightness 40-50lm
Aliexpress
There’re some similar (or not) items on Aliexpress
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 China. There are no active coupons for this product, but the price is pretty low isn’t it?
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): SUN20, 502C6B, 122280, BGRU202, 9eb9a9, vipupgrade8, 15793f, TTxBG10, BGLIG49, BGissam188, BGss8%hl, AFfbG10, BGNIG134, BGST13, BGSO149, BGBINKUPON202, BGBFAFF2019, BGSSLRA, BGCITYADS2019, bGpAnDacHeCk, BGNS139, BGTY34Y, 0e7f33, BGHOMEG12, BGAFF7OFF, BGAFF10OFF, bGhOnEy10, BGTFD54, BGSOTHING25, BGVVDCF, BGLKZZVVDC16, bgshOOp10, BGHome15%, BGHOMEA15%, BgcLuBofErtA10, BGALIBUYMSS, BGDETD202, BGDEFO202, BGCuponation10, 13f142, BGHONEY2110, BG10OFFAFF, BGwhielabel, BGLIG12, BG10OFFAFF1, BGTYOB202, BGd0b05d
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi Sunny Smart Sensor Night Light.
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)).