Aliexpress
Click here… to search for VIVIBRIGHT GP80 1800 Lumens Projector on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. We have found one coupon for this product!
Link: Banggood product page
Coupon (256.40 USD): BGAProjector
(CouponsFromChina.com tip: apply code in your basket (cart) after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): TECH8%, PICODICOM, aff7off, BG3CSUM, BGaDmITAd, bgchinafest, BGBFAFF2019, BGCITYADS2019, Email5, bGhOnEy10, BGdragonBoat, BgoFErTaSchInA10, BGAFF7OFF, 7bcdf9, BGProjectors
(these coupons are old, so probably won’t work)
Price history and price alert
Here is price history (for all/most countries) for VIVIBRIGHT GP80 1800 Lumens Projector.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).