Aliexpress
Click here… to search for Xiaomi Mijia Sherlock M1 Door Lock Left Opening on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (75.39 USD): BGE13
Coupon (77.99 USD): elec
Coupon (77.99 USD): AFfbG10
(CouponsFromChina.com tip: 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
Old coupons (from the oldest to the newest): 502C6B, 127330, ChinaGB964, e2bcea, 2019SPEDM, BGalibuyM1, BGDlzMijia, BGSLM1, BGBFAFF2019, BGCITYADS2019
(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 Mijia Sherlock M1 Door Lock Left Opening.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).