$17.99 – Xiaomi Mijia Hygrometer Thermometer Pro (Banggood, Aliexpress: Xiaomi Mijia Smart Temperature Humidity Pro Electronic Digital Clock Watch E-link Thermometer Moisture Meter Work Mi Home (the best price with coupon)).
You can get Xiaomi Mijia Hygrometer Thermometer Pro for $17.99 using coupon code (in Banggood). Go down and check coupons out. Remember to check price history if it is available. What is the best price?
Latest price update (UTC time):
Banggood ($17.99)
Banggood warehouse is located in China. Is it good price? Maybe there’re no more promotions for this item, because current price is higher than average (which is equal $16.94) I am tired of searching coupons, but I found one for you…
Link: Banggood product page
Price without coupon: $20.49
1. ($17.99): BG2e4d2f
coupon code has to be applied in shop’s 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/feV
Old coupons (from the oldest to the newest): BG81309f, BGM1TOOLS88, BG05f151, BG20236Tool, BGTOOS729, BG31a67a
(there’s a little possibility that old coupon will work)
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi Mijia Hygrometer Thermometer Pro. The lowest price was: $15.99.
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)).