Aliexpress
Click here… to search for XLPower 520 XL520 RC Helicopter Kit 1100KV 4020 on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. Too bad there’s no coupon right now in Banggood.
Link: Banggood product page
Price: -3 USD
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): bgssaff9, BGX52015, AFfbG10, 502C6B, BGXLP52015, BGCITYADS2019, BGXLP15, BG520XL15, BGVDay10%off, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BGheli10, BgoFErTaSchInA10, BgcLuBofErtA10, BGCuponation10, BGDAVIS, BGHONEY2110, BGMATT7
(probably won’t work, but you can try them out)
Price history and price alert
Here is price history (for all/most countries) for XLPower 520 XL520 RC Helicopter Kit 1100KV 4020.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).