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Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. There is one coupon right now! Check this out.
Link: Banggood product page
Coupon (179.44 USD): 00c906
(CouponsFromChina.com tip: apply code in your basket (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): aff7off, bgchinafest, bGpAnDacHeCk, BGHOMEAPP, BGAFF7OFF, BGdragonBoat, BGHCLE15, bgshOOp10, BGHome15%, BGHOMEAPP13, BGHOMEA13, BG11SHOP, 7bcdf9, BG10OFFAFF, BGwhielabel, BG10OFFAFF1, BANGGOODSD
(there’s a little possibility that old coupon will work)
Price history and price alert
Here is price history (for all/most countries) for Deerma CM2200 UV Anti-Dust Mite Vacuum Cleaner.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).