Resolution 1080*2340 FHD+, CPU Qualcomm Snapdragon 855, Type AMOLED, RAM 6GB, up 2.84GHz, 5000mAh(Built in Polymer Battery), GPU Adreno 640, OS Redmagic OS 2.0(Based on Android9.0), Octa Core, Display Size 6.65 Inch 19.5: 9 Oversized full HD Screen, ROM 128GB.
You can create price alert here, copy coupons and view price history. You probably want to know what is the best price?
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.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($464.99): od7off
2. ($469.99): affiliate6
you should apply the coupon in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): BGRM36, aff7off, bgssaff9, BGKtechredmagic
(probably won’t work, but you can try them out)
Price history and price alert
Price history (for all/most countries) for ZTE Nubia Red Magic 3 6/128GB is here. The lowest price was: $454.99.
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)).