Aliexpress
Click here… to search for Xiaomi Deerma DEM-535 25W 5L Humidifier on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. There is one coupon available! Pretty cool, huh?
Link: Banggood product page
Coupon (45.36 USD): BGDEER05
(CouponsFromChina.com tip: apply it in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): 502C6B, d8f2bb, f8aaf1, 919c60
(these coupons are old, so probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for Xiaomi Deerma DEM-535 25W 5L Humidifier? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).