Aliexpress
Click here… to search for Deerma DEM-F628A 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 great coupon!
Link: Banggood product page
Coupon (49.49 USD): BGCuponation10
(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): BGF28A, BGF628A, BGHOMEAPP, bGhOnEy10, BGHOMEAPP13, BGHOMEA13, BGDEF628A, 7d18f7
(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 Deerma DEM-F628A 5L Humidifier? There we go.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).