When I was updating this page, then coupon price was $185.99 for HackRF One Portapack H2 1MHz to 6GHz SDR Radio 1.7.4 (in Banggood). Just check coupons out (with price alert and history). What is the best price?
HackRF One Portapack H2 1MHz to 6GHz SDR Software Defined Radio With 1.7.4 Firmware Flashed Metal Case
Latest coupon and price update (UTC):
Banggood ($185.99)
Banggood warehouse is located in China. There are no coupons available at this moment in Banggood. Is it a reasonable price for this item? Well, this price is higher than average price ($180.99)
Link: Banggood product page
Price: $185.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BG573439, BG124578
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
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
Check out price history chart (for all/most countries) for HackRF One Portapack H2 1MHz to 6GHz SDR Radio 1.7.4.
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)).