Aliexpress
Click here… to search for Xiaomi CoClean TK Negative Ion Tower 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 (563.99 USD): 7bcdf9
(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): TTxBG10, bea3e6, vipupgrade8, ML15%Pro, BGHC20, 502C6B, bgshOOp10, BGHB20, BgoFErTaSchInA10, bGhOnEy10, BGSD52469, BgcLuBofErtA10, BGAFF10OFF
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for Xiaomi CoClean TK Negative Ion Tower? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).