Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (58.57 USD): BGGutscheine
Coupon (59.21 USD): BGJON8
Coupon (59.21 USD): BGRCParts8
Coupon (59.21 USD): BGMatt2022
Coupon (59.21 USD): BGToys8
(CouponsFromChina.com tip: you should apply the coupon 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): BGF4P, TTxBG10, urparts12, BGF4PROV2, BGURF4V2, AFfbG10, affbg10, BGF4V2, BG12MRP, BGWKUCF4, Parts8, BGVDay10%off, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BGRC902, BgoFErTaSchInA10, BgcLuBofErtA10, BGCuponation10, BGDAVIS, BGHONEY2110, BGGAL8, Cuponation9
(there’s a little possibility that old coupon will work)
Price history and price alert
Check out price history chart (for all/most countries) for URUAV Crazybee F4 PRO V2 RC Flight Controller.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).