You can create price alert here, copy coupons and view price history. What is the best price?
Working Temperature -20℃~ 80℃, EDS +/-12 kV Air; +/-12 kV Touch, Resolution Ratio 508DPI, Battery 3.7V 310mA, Fingerprint Capacity 20 Sets, Color Black, Net Weight 100g, Standby Time Half a year, FAR < 0.002%, Charging Time 30 mins, Working Humidity 40%RH ~ 85%RH, Sensor Time 0.5s Fast Recognition, White, FRR < 1%, Material ABS + 304 Stainless Steel, Model T6 Smart Fingerprint Lock, Size 98x 26x 15.5mm / 3.86"x 1.02"x 0.61"
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 and price update (UTC):
Banggood
Banggood warehouse is located in China. I am tired of searching coupons, but I found one for you…
Link: Banggood product page
1. ($13.99): BGXV139
just apply this code 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): BGXV144
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Here is price history (for all/most countries) for Xiaovv Smart Fingerprint Lock.
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)).