Xiaomi 2nd Generation 20 Inch Metal Suitcase (Banggood, Aliexpress: Material in the box Polyester fiber, Product model LXX10RM, Product capacity About 35L, Product weight 4.1kg, Box surface material Aluminum alloy, Cabinet size 486×356×215mm, Total size 551×388×215mm (the best price with coupon)).
Basically copy coupon, view price history or create e-mail price alert. Let’s see what best price is ATM.
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($251.99): bGhOnEy10
2. ($251.99): BGMISHCOOL
3. ($251.99): BGHALLOWEEN
paste coupon code in your cart and click Apply 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): BGTRIP01, bgshOOp10, BgoFErTaSchInA10
(there’s a little possibility that old coupon will work)
Price history and price alert
Here is price history (for all/most countries) for Xiaomi 2nd Generation 20 Inch Metal Suitcase. The lowest price was: $219.99.
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)).