Is the V700 Neo good for a bright living room?

No. It has no official brightness rating and a 1000:1 dynamic contrast ratio, so it looks best in a dim or dark room. Daylight or strong lamps wash the picture out.

Do I need a streaming stick with it?

No. Google TV is built in, so Netflix, YouTube and other apps run on the projector itself over dual-band Wi-Fi.

How big a screen can it throw?

From 40 to 200 inches diagonal at a 1.35:1 throw ratio. A 100-inch image needs roughly 3 meters of distance from the wall.

Does it have a battery?

No. It runs only on AC power, so plan an outlet near where you place it.

Can I connect a soundbar or console?

Yes. It has HDMI, AV and USB inputs, Bluetooth 5.1 and a 3.5mm audio output. There is no optical audio port.

Is it worth it over a 4K projector?

If you mostly stream in a dark room and want built-in Google TV, the 1080p picture is enough. A 4K model costs more but gives sharper detail and usually better contrast.