Motion AI - Detection and classification of entities

Wow! This is exhaustive. I have so many questions, but the most important ones:

  1. how many cameras can this reasonably support on a Pi4?
  2. how much latency for detection events have you noticed on a Pi4?
  3. Does it make sense to have an entire HA instance dedicated to this or should my regular installation support most of this?
  4. Do you use any kind of NVR separately from this?