Potensic - ATOM SE

Potensic Atom SE or LT are the best you're going to find for your budget. Camera is decent but not the best (though certainly better than the cameras in a phone), and you won't get a three axis gimbal so video may be a bit jerky, but these drones fly very well and are fun.

The Potensic Atom SE has been good for me.

I have spent lots of time researching, and here is my take: Potensic Atom - good, budget friendly ($350 for FMC). Comparable specs to DJI Mini 4K and has added benefit of Follow Me and Waypoints. DJI mini 4K - DJI is more well known branded - $450 (FMC). Good specs, not as many features as Atom, but it is DJI I went with the Atom, just based on price, and I don't need to have a DJI. That being said, first flight out it was daylight, and I couldn't see my phone screen worth a damn. So, boxed it back up and sent it back. Got DJI Mini 3 FMC with the DJI RC (with screen). More than my budget, but I don't like the mobile device as the screen, so I spent extra. Regarding your other question: lots of info in this subreddit on what has to be registered and what doesn't. You need to do some research on recreational and TRUST certification (most likely your situation), if in the US. Other countries have different rules, so no one simple answer.