How many types of hosts are there?

We’ve seen: - animal replicants; - the early host models, like the obviously artificial Old Bill and the presumably limited Sector 17 cottage residents; - easily-detectable hosts, e.g. with embedded plugs like the Woodcutter’s satellite transmitter or BunkerHostNumber3’s mesh interface; - harder-to-distinguish hosts.

For the latter ones, one would think the Operations/Extraction teams have portable detectors for the CPU, energy source, C6 explosive, mesh traffic, etc.

Especially since Maeve and Dolores seem able to distinguish androids from humans (and arguably Bernard also, as I would imagine Ford lifted his doesn’t-look-like-anything-to-me restrictions once his artificial nature is revealed).