$99.99 – Tuya Smart WiFi Home Alarm System Kit (Banggood, Aliexpress: Relative humidity: <80%Rh (no condensed), GSM system: 850/900/1800/1900MHz, Reserve battery: 3.7V/500mAh lithium battery, Work temperature: 0 ~ 55 ℃, Alarm number output: <500ma, Working voltage: <120mA, Wireless frequency: 433 MHz, Wireless code: EV1527, The current of the aircraft: <10UA, Input voltage: DC5V (Microusb standard interface power supply), WIFI system: IEEEEE802.11b/g/n wireless standard (the best price with coupon)).
According to my DB the lowest price is $99.99 for Tuya Smart WiFi Home Alarm System Kit (in Banggood). Price history, coupons and price alert are available on this page. Do you want to know what the best price is?
Latest coupon code price check (UTC time):
Banggood ($99.99)
Banggood warehouse is located in China. I have no active coupons for you right now. The question is – is it a good price? Maybe there’re no more promotions for this item, because current price is higher than average (which is equal $84.99)
Link: Banggood product page
Price: $99.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BG4e7b81, BGSaleAD, BG92f5fd, BGMARCHSALE, BGAUGUST8, BGCAPITALOS8, BG8FORMULAMX
(I don’t think these’re gonna work, but you can try ’em out anyway)
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
Do you need price history chart (for all/most countries) for Tuya Smart WiFi Home Alarm System Kit? There we go. The lowest price was: $84.99.
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)).