System: GUMI base on Android 5.1.1, CPU: Mstar 6A928 Cortex-A17 Quadcore (Physical Freq. 1.4GHz, Optimized Freq. 1.75GHz), GPU: Mali-760MP4, RAM: 3GB, ROM: 16GB, Resolution Support: 1080P, 4Kx 2K.
Basically copy coupon, view price history or create e-mail price alert. Let’s see what best price is ATM.
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 code price check (UTC time):
Banggood
Banggood warehouse is located in China. There is no active coupon in my database right now (for Banggood).
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Additional Banggood coupons: first page and second page
Price history and price alert
Do you need price history chart (for all/most countries) for XGIMI H1 DLP Projector? There we go. The lowest price was: $629.99.
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)).