Xgimi's MoGo 4 lists for $500, but its price goes lower during sporadic flash sales, and I recommend getting the version that comes with the Powerbase pedestal stand that includes an integrated battery to extend battery life to 5 hours and makes it easier to set up the projector and to project on a wall or screen (you don't have to find a table or something else to place the projector on). The bundle cost about $50 more but is worth it.
The 2.9-pound Mogo 4 isn't the brightest projector with a 450-lumens rating, but it's reasonably bright for a battery-powered portable projector and I liked the image it projected in a darkened room (the picture is fairly sharp and the colors pretty vibrant). It has 1080p (full HD) resolution and is powered by Google TV, which is better than Android TV and allows you to use the Netflix app on the projector (as well as many other streaming video apps).
While I wasn't blown away by the performance of this projector (you can only expect so much from a projector that's the size of a coffee thermos), but what I liked about it was how compact and versatile it was, especially with the Powerbase's added battery life, and the ability to swivel it up and down and project on a ceiling while you lie in bed. Note that Xgimi also makes a laser version of the projector that's brighter (550 lumens) and will offer a slightly better picture. It's currently on sale for around $600.