Ask HN (again): What is the best affordable programmable drone?

This question was asked on both 2015 & 2016 in HN. I would like to ask it again today to know what are the newest options for this.

Q: What would you recommend as a reasonably priced (sub 150$) quad-copter/drone, that has a camera, the ability to be programmed (so that I can process video/write my own stability algorithms for it), good range, and reasonable flying time? In the event nothing fits that price point, any pointers on what the state of the art is?

Thanks!