Aliexpress
Click here… to search for YEPO 737A6 6/256GB J3455 Laptop on Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. Only one coupon available!
Link: Banggood product page
Coupon (285.88 USD): Email5
(CouponsFromChina.com tip: put item in your cart and apply coupon code there 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): A66G02, A66G025, Wholesale20, BGYE124, BGA6256, aff7off, BGA35171, BGYE5171, BGYE1171, BGYE73756, wholesale20, BG511244, BG5112441, BGYEP1, BGYEP2, BGYEP3, BGYEP9, BGYEP10
(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 YEPO 737A6 6/256GB J3455 Laptop.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).