Basically copy coupon, view price history or create e-mail price alert. Do you want to know what the best price is?
Screen resolution 1920x 1080 (FHD), Screen size 12.5 inch, GPU Type Intel HD Graphics 615, CPU Type Intel Core i5-8200Y, Hard Disk Memory 256 SSD, RAM 4GB
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. We have found one coupon for this product!
Link: Banggood product page
1. ($822.49): Email5
apply it in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGXMMI1, BGCITYADS2019, BGXMMI2, Wholesale20, BGMPB2020, BGAFF10OFF
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi Mi Laptop Air 12.5 i5-8200Y 4/256GB.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).