Aliexpress
Click here… to search for Xiaomi Deerma DEM-MW200 Electric Insect Killer Lamp on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (60.58 USD): bGhOnEy10
Coupon (60.58 USD): BGHome15%
Coupon (60.58 USD): BGAFF10OFF
(CouponsFromChina.com tip: just apply this code 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): e2bcea, 502C6B, 296acc, 25repel, vipupgrade8, rotterDEM, TTxBG10, BGDEER05, BGss506, bgssaff9, AFfbG10, BGDE29, aff7off, BGBFAFF2019, BGCITYADS2019, BGBGHFRI15, BGVDay10%off, BGHOMEG12, BGMPB2020
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi Deerma DEM-MW200 Electric Insect Killer Lamp.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).