Price history, coupons and price alert are available on this page. Let’s see what best price is ATM.
Contrast ratio 3000: 1, Uniformity of illumination 70%, Physical Resolution 1920x1080dpi, Product Color White, Aspect Ratio 4: 3/16：9, Display Technology LCD display, Focus Manual, Max Compatible Resolution 4K (HMDI Mode）, Lamp LED, Nominal Brightness 6000 lumens, Throw ratio 0.75, Lamp Life 50000 hours
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($252.44): BGPROBuscape
2. ($267.29): BGAProjector
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/5cd
Old coupons (from the oldest to the newest): 7bcdf9, BGANAK8, BGProjectors
(system checks these coupons on every price check (like once per 24 hours), but you can check them out anyway)
Price history and price alert
Price history (for all/most countries) for AUN AKEY8 1080P Projector is here.
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)).