Aliexpress
Click here… to search for LANGFEITE L11 20Ah 36V 500W Electric Scooter on Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. Well, there is one coupon available right now.
Link: Banggood product page
Coupon (1011.59 USD): BG71c041
(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): cfa1d4, PICODICOM, picodicom, 5d1752, Wholesale20, bGpAnDacHeCk, 7bcdf9, BGSS20SW, BGAFF7OFF, LFTL119C, BGEBSC15, BG01b49c, 00c906, ERidingMarch, 2203ActiesNL, tRaDetRaCKeR, 8wEbgaInS5, pROMo8cuPoN
(these coupons are old, so probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for LANGFEITE L11 20Ah 36V 500W Electric Scooter? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).