It uses DDR4 2133/2400 SO-DIMM memory. Maximum memory configuration is 32GB. I don't know the exact model of the 8GB that's already installed, but before any upgrade, I'd buy a kit of 2 anyway, to ensure they are compatible and run in dual channel. Something like this -
https://www.amazon.com/dp/B01DGOF6WS/ref=twister_B077C1Q198?_encoding=UTF8&psc=1 $190 for a 16GB kit and $360 for a 32GB kit.
Also checked the manual, looks like upgrading ram won't be that easy. For some laptops, it's a couple screws on the backside and a small panel comes out and you can easily upgrade ram by just inserting, quick and painless 5 minute job. But this laptop will need a complete disassembly. (I've done it before, it's a hassle if you do it the 1st time).
I'm not sure about it being the best in its price range, except what I wrote above. But if it costs whopping $850, it should have easily upgradable RAM, imho.