Right now the best price with coupon code for Smart WiFi Circuit Breaker with Remote Control is $13.99 (in Banggood). Basically copy coupon, view price history or create e-mail price alert. You probably want to know what is the best price?
Smart WiFi Circuit Breaker with Remote Control Voice Activation Adjustable Over Current Protection Energy Metering Easy Installation for Efficient Home Power Management
Latest price update (UTC time):
Banggood ($13.99)
Banggood warehouse is located in China. I have no active coupons for you right now. Is it a reasonable price for this item? From what I can see this price is higher than average price ($13.74).
Link: Banggood product page
Price: $13.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGdbdf64, BGd3373f
(probably won’t work, but you can try them out)
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Price history and price alert
Here is price history (for all/most countries) for Smart WiFi Circuit Breaker with Remote Control.
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)).