Operating System: Android 8.0, CPU: MT6797 (Helio X20) Deca Core, GPU: ARM Mali-T880 780MHz, 10.1 inch 10-point Capacitive Screen with 2560x 1600 Resolution, 4GB LPDDR4 RAM for Advanced Multitasking, 64GB eMMC ROM Storage Capacity.
Basically copy coupon, view price history or create e-mail price alert. 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 price update (UTC time):
Banggood
Banggood warehouse is located in Hong Kong. I found coupon for you. Check this out.
Link: Banggood product page
1. ($167.39): aff7off
you should apply the coupon in your 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/i1u
Old coupons (from the oldest to the newest): c0fb46, 518b5b, e9f6fe, FE68C1, BG17b05d
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Price history (for all/most countries) for Chuwi Hi9 Air 4/64GB Tablet is here. The lowest price was: $139.99.
Price records source(s): Gearbest, 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)).